What is the best Airsoft gun for beginners?

I played Airsoft at my friend's house once, and it was really fun. We did a zombie game, and I used the small Crosman Pulse M74DP and it was pretty good, but I want a better Airsoft gun than that. If there are any must-have Airsoft sidearms, that would be awesome if you could list that as well. My price range is under $50, but if it's a little bit over like $60 I can still afford it.