Welcome to Million Miler Reviews, a new series of product reviews with a big focus on how a given product survives a life spent on the road. I won't review something until it's gone around the globe with me at least once.

When you travel as much as I do (201,890 miles last year, 143 days away from home), every single thing you take with you becomes a major consideration. I can list out to you every single item in my bag, and I regularly reconsider each item’s necessity, its volume, and its weight. If there's a lighter, smaller replacement for a cable or charger or even a paper notebook, I'll be right there to upgrade.

And so, committing to buy a set of Sony WH-1000XM6 (henceforth just XM6) headphones, given their eye-watering $450 price and considerable size, was not a decision I made lightly. But buy them I did, and I loved them too. They’ve been around the world with me countless times. And then, 308 days after I put them into service, they broke.

It wasn't until quite recently that I would even consider traveling with wireless over-the-ear headphones. Yeah, they sound great, and most offer some stellar battery life, but they're so massively bulky that I couldn't see myself giving up the space in my bag to bring ‘em along.

Instead, I traveled with my trusty Shure SE535 earbuds, which not only offer world-class sound but also feature a foam design that means I literally can't hear anything in the world around me when I put them in. They're blissful, and they’re tiny, but the True Wireless adapter I got only managed eight hours on a charge when new. A few years on, that's down by about a third, no longer good enough even for your average eight-hour trans-Atlantic flight.

That's what got me looking for new options last year, and it just so happened that Sony’s then-new XM6 had just dropped. My friend Billy Steele gave them a rave review at Engadget, and they seemed to offer an incredible set of features. They also looked comfortable and, at 254 grams (roughly the same as an average paperback), they wouldn't weigh me down too much.

So I took the plunge, splurged on a pair for myself, and immediately fell in love.

I wouldn't call myself an elite audiophile. I run lamp cord to my speakers instead of something that costs $200 a foot and features tritanium-plated connectors and unobtanium shielding.

That said, I do appreciate good sound quality and am happy to pay the extra for it. For example, I run a PS Audio Sprout100 with a pair of Klipsch reference speakers for tunes in my home office. World-class audio? No. Way better than a pair of powered speakers plugged into my motherboard's 3.5mm output? Yes.

For me, the XM6 headphones sound very good. They are not the most powerful headphones I've ever experienced when I'm listening to punchy tracks like No Excuses from Alice in Chains or bass-forward tracks like Oi-1 from Biosphere, nor do they offer the most finesse in more nuanced songs like Tracy Chapman's Fast Car, possibly the greatest test track of all time. Still, they offer stellar all-round sound.

I never found myself wishing I'd paid more for something better.

There’s no delicate way to say this, so I’ll just lay it out there: I have a big head. It’s seven and three-quarters if you're familiar with hat sizing, and so it's often difficult to find cans that fit me comfortably. That's another reason why I really like my Shure buds. They’re totally unaffected by my cranial expanse

A lot of headphones bind uncomfortably, but I was immediately impressed at how well the XM6 fits my head. Yes, I need to extend those arms all the way, but the lightweight construction and the foam padding on the headband make for something that's quite comfortable to wear for hours and hours at a time.

The cups are similarly plush, with a closed-cell foam surround that comfortably conforms to my head. Those cushy cups aren't just for comfort, though.

Everyone talks about active noise cancellation (ANC) as if it's the end-all, be-all feature of over-the-ear cans for travel. It's important, don't get me wrong, but a good set of travel headphones starts with good noise isolation: passive blocking of the world around you, before you even power them up.

While not as isolating as my Shure earbuds with their memory-foam tips, the XM6 still impress. Put them on in a busy space and suddenly the world around you gets a little less stressful, something that's key to me. I spend much of my time wearing these in places like CDG, among the most sweaty and stressful airports on the planet.

But turn them on, and that drone of humanity around you just disappears into the background. The XM6 really does a stellar job of negating noise, delivering extremely competent ANC without a trace of the hiss you can get on lesser noise-canceling devices.

That comfort and ability to dial down the decibels of the world is part of what charms me about the XM6. Putting them on after I get through airport security is almost like wrapping myself in a safety blanket. My day instantly gets better.

I wish the case were smaller, and I really wish that it collapsed when empty, but it has a slender design and I appreciate the clever magnetic closure.

The headphones themself are mostly easy to manage while hustling from terminal 2E to 2G. Swipe forward or back to skip tracks, up or down to adjust volume, or tap twice to play or pause — settings that can all be customized through XM6’s dedicated app. You can even set them to dismiss phone calls just by shaking your head.

Take them off, and they'll automatically pause whatever you're listening to or playing, and they even make for a decent Bluetooth headset for calls. Even in busy spaces, people rarely have a hard time hearing me.

If I need to hear the world around me, I can cup my hand over the right can, which triggers the microphones to pass ambient audio through. For longer listening, there's a small button on the left can that toggles ambient sound on and off. This is perfect for when the gate agent is announcing just how long it’ll be before I can get home that night.

Sony even includes a short adapter for using the XM6 wired with airplane seatback entertainment systems, which comes in handy in the rare case you can find something worth watching between the turbulence warnings from the flight crew.

Stellar. Sony promises 30 hours with ANC and, a year later, I'm still getting close to that on a charge. I've worn these on multiple, all-day journeys to faraway places and they've only ever failed me when I forgot to charge them between trips.

And even then, 3 mins on a USB-C port is enough to pull down the juice required to get me through a three-hour flight. That’s remarkable.

This is, sadly, where it all falls apart. Before I bought these, I read up on their predecessors, the XM5. They got almost universal praise, but I read a few instances of people suffering broken hinges. Though I was early in getting my XM6 headphones after their release last year, there were already a few reports of similar failures.

Given all that, I treated these things with care, gently folding and unfolding them to put them in and take them out of their case. I never dropped them, never strained them, and lived in fear of them breaking. Given their light weight, they do have a fundamentally flimsy feeling about them, one that sadly proved accurate.

Just this past week I noticed the right extension area on the top had cracked, a loop of plastic. At first I thought it was just cosmetic, no big deal, but I quickly realized it serves a functional purpose. With that piece broken, the right earpiece isn't held tight, causing it to swing outward, as you can see in the photo below.

Everything still works. Indeed, I'm wearing them right now (listening to Jeff Buckley, if you’re curious), but because the right earpiece isn't held in place, noise isolation in that ear is dramatically reduced. I can hear too much the drone of the tired old A330 that’s shakily hauling me across the Atlantic.

I'm hoping I can maybe patch things up with a zip tie, but frankly, this is pretty unacceptable on a device this expensive and less than a year old. My wired Sennheiser HD555 over-ear headphones, which I paid $377.70 for 16 years ago, still sound great and look like new.

Yes, I've probably put more time into my XM6s in the last 11 months than most people will in a lifetime, but I’m really disappointed, especially given how carefully I’ve treated them. I knew their non-replaceable batteries would die some day, but I'd hoped to get at least five years out of them.

So, it's a shame, but I can't recommend these. In addition to small and lightweight, a good travel device needs to stand up to the rigors of the road, and these have failed in that regard.

I'm hoping I can DIY up a fix for mine, otherwise I'll be back on the market for something new. Maybe I'll go back to Sennheiser this time. The new Momentum 5 sure look nice, but they do look awfully big.