I had previously bought some screen protectors from ebay for my Sensation XE, however, they were a bad fit due to the curved edges of the screen.
I then bought a set of these ones directly from Amazon and not one of the 3rd party sellers on here so I could be confident they were the genuine HTC product. Sure enough when these arrived they were a perfect fit.
In the package you receive 2 screen protectors, hopefully you should only need 1 unless it goes wrong on the first attempt. Before you peel off the back, make sure you position this on your screen so you know where to stick it, you will have about a 2mm gap all the way round the screen. Also you need to ensure there is no dust or grease on the screen as you will get air bubbles you can't remove if there is. Once you first apply, any air bubbles should push out with a piece of card or similar.
These are a great fit on the Sensation XE and went on without any bubbles. Also a much better quality one than you will get on ebay or similar. It is worth spending the little bit extra to get the genuine product to make sure they fit, especially with curved / raised edges of the screen on the phone.