The great thing about the silacrylic case is that while it's two pieces is feels like a single piece once it's on and rather than most cases the cutouts are positioned for the one xl and not the one X.
Unless you are looking for a paper thin hard shell case (never saw the point in them) then you will love the silacrylic case. Protects the camera, there is enough of a lip that if it falls face down on a flat surface the screen won't get a scratch, the hard shell covers the back and all four corners (points where impact will cause the most damage) and the silicon shell gives you perfect use of the power and volume buttons. The buttons actually seem easier to push with the case on. One thing in didn't see mentioned about the case is that the cutout for the usb slot is actually big enough to handle the larger square cords and not just the smaller ones like the stock cord.
If you don't mind a little extra bulk (I prefer larger screen phones to not be so thin. Hard to handle for me) then this is without a doubt the best case you can get for the one X.
If you want thin tpu case either get the driztronic or cruzerlight cases. Just don't get the white or clear models. They get dirty or discolour really fast.
I liked the speck candy shell, but holy crap is that a monster to take off. Make sure you don't need to access the simcard slot after its on. You will feel like you are going to snap your phone in half trying to get it off.
In have owned a lot of cases for the one X, from cheap tpu cases from china, to higher quality ones from cruzerlight, case mate cases, otterbox and now the incipio silacrylic case. If you want the case with the best protection without adding too much bulk then you have to get the incipio. Best case I have had for any phone.
Sent from my One X using xda premium