I don't mean to pick on the OP here, but in general I don't have a lot of sympathy for folks who get home from the store with their new gun and find all sorts of stuff wrong with it that they could have seen before paying for it.
I have had salesmen bring out two or three different samples of the same gun so I could pick the nicest one. If the one on display looks rough from customers handling it, I ask them to bring out one that's still in the box.
It's not like you're buying a bag of M&M's. It's a firearm that you may want to keep for life and even hand down to a child or grandchild. It normally costs anywhere from $300 to $2,000. It's not being picky, but just smart.
If a store seems impatient, find a better store.
Lastly, I've been to stores that simply take a defective gun back and give you another one. They take care of the problem so you don't have to worry about it.