Not bad at all... I've had three surgeries, have had more than my share of IV's and frankly, compared to the rest, wisdom teeth was a cakewalk.
Sit down in the chair, doc will tell you what's going to happen, they gas you up, then insert the IV, and then you start counting backwards. Struggle to stay conscious, you shouldn't make it past 95... that stuff works WONDERS.
I woke up after the surgery, said some really funny things, and was on my way. I have sporadic memories that day and the day after from the drugs. The worst part about the surgery is being conscious of your diet for a bit after that.
Like I said, it's a cakewalk. The people who put in the IV's do it ALL the time, they're perfectly safe. I hate needles more than the next guy but you gotta realize, that needle in your hand/arm is the reason you're high as a kite. After that, you learn to enjoy the IV.