With it being so large, it's somewhat imperative that the HTC Sensation XL's screen also performs quite well. Unfortunately, while it's not bad, it's nothing special. Its chief problem is its lowly 480 x 800 pixel resolution that gives it a pixel density figure of approximately 200ppi. While this may not sound all that much lower than the 256ppi of the Sensation XE (which packs 960 x 640 pixels into a 4.3in display), it is clearly much worse than the 330ppi of the iPhone 4 and 4S, and the difference is noticeable.
The upshot of this is a display that, while it would be a slight exaggeration to say it's out and out grainy, is notably softer than rivals, and simply can't pick out as much detail. This is particularly obvious when viewing a webpage where you simply can't make out text when zoomed out. Conversely, if you have trouble making out the fine details on small screens anyway, you may actually find the larger XL is easier on your eyes.
Either way, if you can see passed the low resolution then this is a good LCD display. It's bright, has good viewing angles and produces really rich and vivid colours. Combined with its size, this makes it a great video viewer, though as HTC continues to offer fairly poor video playback support (mp4 and avi will play but divx, mov, mkv or rmvb won't), you'll have to re-encode your clips to get them to play.
The size of the screen also has some ergonomics benefits. If you have large hands and fingers, the larger icons and amount of space in which to work will appeal, and typing in particular is incredibly easy. Even we, who are used to typing at speed on smaller screens, found the extra space on this phone rather welcome, and could rocket along when bashing out some words.
This speed is in spite of the phone only running a single-core Qualcomm Scorpion processor. In actual fact, the chip runs at 1.5GHz, so it's noticeably nippier than your typical 1GHz mid-range handset but nonetheless it's behind the dual-core models sported by the likes of the Samsung Galaxy S 2 (1.2GHz) and HTC Sensation XE (1.5GHz).
It's less that you necessarily need the power now but if you're investing in a two year contract and you want a premium phone, picking one that's behind the curve already isn't the best bet.
Running a quick benchmark, the Qualcomm chip proved its raw power by scoring 2889ms in SunSpider, beating the 3780ms of the 1GHz HTC Rhyme but falling behind the 2261ms of the HTC Evo 3D.
In the real world we noticed a few more occasions where the phone would stutter when browsing the web, navigating GoogleMaps or running some graphically intense apps but they were relatively few and far between. Only running Flash video really caused the phone to become noticeably sluggish.