I just got a new road bike - a Schwinn Paramount 8. It's the first road bike I've owned in about 25 years. The bike has Ultegra SL components except for the rear deraileur which is DA.

I really like the bike -it fits me well and is fast, light, and good looking - but I'v got a couple of problems. First, I'm having trouble shifting to the larger chainring and get "chatter" with certain gear combos when I can get to that chainring. I noticed this right away and took the bike back to Performance. The "head" of their service department disparaged the build it had received originally. (It had been built at a different store and then shipped down to mine.) He spent an hour with it to "get everything right." I rode it again this weekend and still have the same problem. It's my understanding that with the Ultegra (and anything modern) the shifting should be fast and clean and quiet (except the extremes)).

Another issue is that I hear "creaking" when I put the hammer down. Nothing noticeable at normal speeds but when I charge up a hill or accelerate hard I hear creaking.

I guess my question is: should I take it back to Performance and give them another chance to get things right or take by an LBS that is reported to be the best in the city (and is closer) and let them take a shot at it? My main concern is that there's something fundamentally wrong and Performance won't tell me.