Most of my interactions have been with Sabres players because I lived in Buffalo for so long, but I did meet Briant Gionta and Zach Parise. They both came to Buffalo to do autograph sessions at a hockey outlet called Great Skate like a month apart in the Summer of 2010. Both were very nice, but Gionta was more friendly. He took a minute to chat everyone up and seemed really happy to be there (granted he is semi-local). Parise was polite, but it was more of a 'here's your signature, now on to the next guy so I can get out of here' kind of vibe.
I met Pat Kane out at a bar in Buffalo, he was as much of a colossal d-bag as you can imagine.
I met Zemgus Girgensons at a different bar during his rookie season (when he was 19). Dude was trashed. He hopped behind the bar and grabbed a bottle of vodka, then he went around to strangers and topped off everyone's drinks with pure vodka.
One time I volunteered to hand out 50/50 tickets. It's through the Sabres alumni foundation, and my school said that if we volunteered to do it they'd give us free ticket to a future game (which was horseshit, we didn't even get to stay and watch the end of this game). But we all got to meet Larry Playfair, former Sabre and head of the Sabres alumni foundation, who was a riot. Coolest old guy I've ever met. He told me if I ever meet anyone I don't like to give him a call and he'll kick their ass for me.
Then I was out at a bar in Hamburg and met Pat Kaleta, who was very nice to me but was very clearly a douche as well. He bought a case of Blue Light and was just handing them out to random people, including my group of friends. He spent the whole night trying to hook his scrawny cousin up with some smoking hot girls who weren't into it at all.