sounds like hes trying to sell you on what he carries in stock....."polks suck, you should get these Arc Audio speakers...btw, i have these in stock. I can give you a great price with an amp/speaker/hushmat combo." sound familiar
Call him up (as another potential customer, maybe you drive a 350z) and try to get the same thing and see what he says. IMO, thats a good way to tell if the shop is legit or not. Not their quality of work, but at least if they are trying to do this to your b-hole