I think you should definitely buy it. The story isnt as good as the first but the gameplay is still really fun. But don't go into it expecting an experience better or just like the first, treat it as just another game. That way your fun wont be spoiled no matter what seeing as its a good game on its own. :)
I do not own a 360 but I spend a great deal of time playing my friend's console. I really do not enjoy that controller. The nubby surface of the thumb sticks make my thumbs feel sore. The locations of the d pad and analog sticks just feel awkward. And the general shape of the controller feels kinda clunky to me. But the PS3's duelshock 3 feels perfect, almost like it was made just specifically for my hands. For me, the locations of all the buttons feel natural and I can easily access everything without feeling awkward. And I actually do like the triggers, I think they feel fine. But of course, this is just my personal experience with these controllers. One controller is not necessarily better than the other, it's all about preference. ;)
Wow, if you think Splinter Cell is kind of a strange game to be scared of then you'll get a kick out of mine. When I played Super Mario 64 as a kid, the under water level with the sunken ship and the eel scared the shit out of me... and it still does lol But for more current games, Bioshock definitely had its moments. The Sander Cohen level with the rooms full of posed corpse sculptures gave me the creeps. And I screamed for a few of the good jump scares ;) Also, while Deadspace was a bit scary, I would describe it as more stressful than anything. The sound effects were so loud and abbrasive that after a run in with a few necromorphs, I was more relieved by the silence than the fact that the character was still alive.