Was very satisifying, an definitely filled my need for some TS.
Gameplay: if you played any of these games before, expect nothing less. it has some great level designs and keeps you entertained on hours on hand, and the fact that u can compete for a high score online, increase difficulty, and has a Co-Op option makes it extremely replayable.
Graphics: very reminiscent of Second Opinion, but thats always good. There's nothing I can complain about it, but I liked the more realistic textures of Under the Knife, now everything is neon purples and blues, kind of takes you out of the realism.
Story/Dialogue: the fact that all the people now have full dialogue is nice, and the voice work is pretty descent, I can't complain or praise anything about it. The story is abit lacking, but then again I'm just here for the surgery, not the mello-drama in it :)
Difficulty: This is a very touchy subject for people. For some, its extremely hard and it takes them four tries to get past every level and gives them wrist cramps. for others, it's extremely easy and they just go straight through the game with no trouble (Although some who claim this might actually be lying) But for me, I find a very middle ground expierence, where the difficulty is high enough to give me a chalenge, but I'm able to do it first or second try. I will admit though, some levels are dastardly.
All in all, I see this game, as like the other Trauma Center games, as probably a training game for your skills in dexterity. If you can complete this game, you should be able to kick the ass out of Metroid Prime 3, Resident Evil 4, or any other shooter like game where your pointing a dot at a screen.