I never had any problems with mine, and i'd never go back to stock. Ever. The throttle response is much sharper and more responsive than stock. The edelbrock is very easy to get fine tuned, and designed really well so taking it apart and putting it back together is easy if you need to swap out the needle or clean it out. Mine starts and idles better than it ever did with the stock carb, and it doesn't even have a choke to mess around with. It does have a decent power gain, but the power gain is not as noticable as the other benefits, and wouldn't be worth the money if you were getting it for just the power alone.
For a good exhaust, there are quite a few good choices, depending on how loud you want it, and where you want your gains to be (low, middle, top, or all around). You'll hear people recommend HMF a lot, and I like mine, but it's loud and the gains are mostly in the low end so it's not for everyone.