Before we started dating, my fiance went into Penn Cycle to buy a hybrid bike for commuting. They told her a specific model could easily fit a rear-rack. She bought it. This wasn't true. When she went back and talked to the very same saleperson for a rear-rack later, he told her it wouldn't fit and would require some extra work. Even then, it still might not work. That was frustrating. Recently, she decided she wanted a road bike so, while still not happy with Penn, wanted to check them out for prices. They kept trying to push her to lower quality bikes that I think were overstocked and wouldn't really explain any of the features. We went elsewhere pretty quick. We got better service in every other bike store we went to. I won't consider Penn again.
Pros: possibly price, if they have exactly what you want at a cheaper price
Cons: misleading, either ignorant or disinterested salespeople