I don't think there's anything wrong with the Wii version. Then again, I haven't played other Splinter Cell games, just the (rather) old Rainbow Six games. The only thing I had a problem with was the style of aiming. It was a little awkward to control, as when you had to aim at a small camera or a trip beam source, it took me a while.
There might have been options to modify sensitivity, but that's what I can tell you from my limited (an hour or so) gameplay. Other than that it was good. I'm probably going to buy it from Overstock soon, but I just bought Super Paper Mario, so I'm going to hold off until after I get a good chunk through that...