Speedtech is by far the best shop. I give them first shot at all of my business. If you go to Ultimate, make sure you ask for Paul or Gary. Most of the other guys are completely useless.
As far as some employees not being familiar with your brand, think about how many different rc companys are out there. Nobody is going to know everything about every product.
If you are on this site, you obviously have a computer. Do yourself and evryone else a favor and look up the part numbers that you need before you head down to your local spot.