Having lived in Houston for a year, I enjoy the large number of gun shops in town. I've always enjoyed myself in the different stores, but each place can have its own personality that I think it is important to consider to try to have the best time possible.
Collector's really is in a category of its own. Some of the radio ads mention it as the "best gun show in town", and they're not kidding or exaggerating. The sheer variety and quantity of guns in that shop is staggering, and a lot of the inventory is out on the show floor, available to pick up and handle. It's hugely entertaining to walk around the store and just see what's there. For the store to do so much business in such a variety of guns, Collector's has to have what I assume is a pretty precise read on the market values of new and old stuff. The price on new, market-saturated guns such as the M&P appear to me to be on the high side, but they also did recently have a HK sale going on. The upside to to such is system is the kind of used and rare guns that are charming to see live and in person.
As a result of the store's reputation, and the general attitude of the staff to encourage customers to handle firearms results in an environment where there's a large number of people looking at and touching guns who don't intend to spend money mixed in with the people looking to buy. The sheer volume of customers is enormous, many are in the act of buying guns, manyare super-knowledgable, many are new, and many are just window shopping. In that environment, considering those conditions, I'd say that Collector's is a store where you're probably going to have drive the interaction with the sales staff.
I know that most of us have specific expectations for our gun shopping experiences. With Collector's being as unique as it is, I think that having unique expectations for shopping in that store would give the best change for mutually beneficial shopping experiences between staff and customers.