There are shops that will treat you nice even though you didn't buy your bike there. AllezGirl's LBS double checked my fit, measured my bike, ordered me new parts and spent hours installing them for only $40 labor. But I also spent more than $400 on parts and accessories and would recommend them to anyone.

I was convinced my stem was too short, but it was actually the saddle that was bothering me. I was always trying to push myself farther back on the seat, and I equated that to the stem being too short. Shop could have profited by selling me a stem, but said it was the perfect size for me and didn't pressure me to buy a new saddle (although I did). With the new saddle, the top tube/stem feels dead on.

You'll have the last laugh by not going back there and not recommending the shop to others.