Hands-on Lenovo's X1 Carbon ThinkPad is the company's flagship business laptop and has just been refreshed for 2017. But the new model may frustrate.

The Reg got its claws on the new model for a couple of weeks, equipped with a core i5-7200 at 2.5GHz, 8GB of RAM, Windows 10 Pro build 1607 and a 256GB solid state disk that said it has 237GB capacity. Your correspondent schlepped it around to conferences and to the office for much of the last two weeks and found a lot to like.

The battery stood out, as I found it possible to get through a day's intermittent work without needing a recharge. Lenovo claims the X1 can run for 15-and-a-half hours on battery alone, and for once that may not be just an ambitious claim.

On one day at a conference I used the X1 for several periods of 30-45 minutes taking notes during conference sessions, a dash to somewhere quiet to work, more note-taking and writing, time in the Reg content management system, and a spot of recreational surfing. Through that day the PC sometimes claimed it had 15 hours of juice. After after five-and-a-half hours of use through the day, all of it on WiFi, I ended the day with the X1 claiming it could go another four hours.

The workload matters, though: later, I used it to stream a 90-minute movie and found that feat drained the battery by nearly 30 per cent, suggesting my day at the conference may have been kind to the battery. Recharging was pleasingly rapid, even when I found an old USB battery pack in my bag and plugged it in to the USB-C port.

The machine's keyboard is excellent. Pleasingly large keys with decent travel made typing easy. I found I was quickly up to speed.

Size and weight are good. The machine weighs in 1.13kg (2.5 pounds), a bit lighter than the 1.35kg early 2014 MacBook Air that's my workhorse. A nicely narrow bezel means theres a 14-inch, 1920x1080 screen that worked well in all light conditions. The speakers surprised, in a good way: the first time I played video I found myself marvelling at the volume and richness of sound.

The X1 also presents some irritants. The touchpad often interpreted a gentle single-finger slide as a two-fingered right click. I initially thought that might be a feature, not a bug and I was right: there's an option to have the bottom-right corner of the touchpad set to always register a right click. But even after I turned that off the mistaken interpretations continued, which was damnably annoying.

There's also a TrackPoint micro-joystick that ThinkPads have used since the 1990s, plus physical buttons atop the touchpad.

Fit and finish worried me: there's a gap wide enough to catch a fingernail between the machine's base and sides. I found I could really get my nails in and dig or pull at the machine (and I'm a once-a-week nail trimmer, so it's not as if I have substantial claws to work into a crack). I don't think the machine will come apart, but fidgety people might do some damage over months of use.

The machine also seized up from time to time, pausing under moderate load for up to 30 seconds. Enlarging windows sometimes defeated Windows' animations, drawing a swathe of black where an expanding document ought to have been.

The X1's also a heavy sleeper: it sometimes took thirty seconds or more to become usable after I flipped it open.

Whether those performance glitches are down to Windows 10 or the X1 is hard to know. Whatever the cause, they aren't welcome and don't represent a premium experience. Indeed, my MacBook Air is two years old, has a three year old design, a 1.4GHz CPU that's years older than the 2017 X1's and still wakes up faster than the Lenovo machine. The MacBook Air does throw a wobbly with about 20 Chrome Tabs, Slack, Spotify, OpenOffice and TweetDeck open, but also has half the X1's RAM … and the X1 threw wobblies under lesser loads.

This year's X1 Carbon is a typically slick device, albeit one that revealed some worrying wobbles when we took it on the road. None were show-stoppers, but in your correspondent's experience PCs hardly ever go better after they've been carried around and used hard for a couple of years.

I handed the X1 back hoping it would be the exception to that rule, because while impressive it also hinted at unhappier days ahead. ®