I don't know about x-com since I don't have it/can't afford it/don't know if it's my kind of game. However, what I do know is when I play any kind of tile-based strategy game, it irritates me to no end when my controller accidentally doesn't select the right tile. If I can just click on the tile it's fine, but if I end up accidentally scrolling past what I want, it wears on me ever so slightly. So, even for something slow paced, I just really like precision and that's my way of handling controller choice. If I can't be precise, then I can't play. That's why I have a small stack of wii games, and I only ever play the ones that use gamecube controllers. Why? Because the wiimote handles precision like somebody with mittens cooking italian cuisine. So... that's my preference. Not gonna say controllers are worse, because sometimes I really do wish I could game while hanging back, which I just can't do. My preference in terms of gameplay outweighs the desire to hang back.