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The Lumia 950 XL is certainly a strong effort on Microsoft's part, but does it really do enough to compete with the rest of the 2015 flagship lineup?
Firstly, it has to be said that the Lumia 950 XL has a great camera. In almost every situation it coped admirably, nearly always turning in great shots, and a few particularly stunning examples.
In terms of general performance, the XL is also a champ. No matter what I threw at the device, it was able to handle every app and game with aplomb. With an lovely 2K screen, watching videos and reading for extensive periods was a treat, and the ClearBlack coating really works well to improve visibility in bright sunlight.
As ever, the Live Tiles of the Windows 10 Mobile operating system are a real draw, presenting glanceable information in an attractive way, and offering something different in what is increasingly becoming a sea of copycat and me-too devices.
With expandable storage I was never in danger of running out of space, even when I exceeded the 32GB built-in limit.
As has been the case for years, recommending Microsoft's mobile OS to anyone comes with a massive caveat: the app gap. Though some strides have been made, many top apps have yet to make their way to Windows 10 Mobile.
What's more, the apps that are currently available tend to be rather poor, and are only infrequently updated; Instagram is a prime example, being still in beta after several years.
Battery life is also something of a let-down. Given the size of the unit, and the general efficiency of Windows Phone in this area, I had great hopes for the endurance of the 950 XL. Unfortunately battery performance was only ever middling at best.
To top things off, the very, very plain design is a let-down set alongside the design pedigree of the line as a whole. Past Lumias defined what was capable with polycarbonate, with interesting, insistent lines and an almost iconic look. By comparison the 950 XL is drab, and more likely to be seen in the pocket of a used-car salesman than a trend-setter.
It's fair to say that I'm something of an apologist for Windows Phone, having flown the flag for the operating system even when things hit rock bottom. And yet, for all the waiting, the Microsoft Lumia 950 XL doesn't feel like it's making the most of the potential offered by Windows 10 Mobile.
The hardware definitely has its highs and lows. Build quality isn't the best around, but handling is great. All of the lovely pixels on the AMOLED screen, along with the exceptional colour accuracy, make it one of the best around, but the speakers are a bit of a let-down.
Only the camera proves to be a real stand-out feature – alhough many of the former staff of the PureView team went over to Apple, clearly enough stayed around to make a difference. As someone who values the camera over almost everything else on a smartphone, for me the 950 XL was a real gem of a performer.
And yet, that app gap will likely be a problem for many users, while the buggy nature of Windows 10 Mobile is likely to test the patience of even the most dedicated Windows fans.
The real question is: after at least 18 months out of the game, has Microsoft done enough to earn a place at the top division once more? And the answer is yes, but with an enormous proviso.
As a device, the Lumia 950 XL, along with its slighter sibling, has been carved out as a tool for the purist. And to that end Microsoft has delivered, and has shown a promise that will likely be glorious when fully delivered on.
For those not sold on the Lumia dream, however, it's a much harder sell. The stark truth is that, for most people, there are better phones out there, especially the likes of the Nexus 6P.
For the faithful, this will likely be enough to keep them going while rumours of the 'Surface Phone' fly around, and perhaps of a replacement for the Lumia 1020.
First reviewed: December 2016
Sean is a Scottish technology journalist who's written for the likes of T3, Trusted Reviews, TechAdvisor and Expert Reviews.