Nah AA3 isn't that bad, its just probably going to lag the fuck out of your computer, and it's still got quite a few bad bugs in it. I uninstalled it a week ago though because I'd rather stick to AA2 right now.
Go ahead and download AA3 if you want, I'll be just a new to it as you I guess, I only played it for like an hour and was like "WHAT THE FUCK IS THIS?!??!?!" because they use a totally new graphics engine and everything.
Shit go ahead and do AA3, its all good.