I think they're fine for the more everyday stuff. The troubles I've seen and heard fo are usually in the more clollectible guns where the finer details can mean a lot in terms of value. Many many sellers don't really know what they're looking at or don't understand guns from the collector's standpoint. I've bought a couple NIB handguns, and a few long guns that werre really good deals. But at the prices I was paying I didn't really care if they weren't exactly as advertised. Having said that you're really taking a gamble if you're talking about guns in the thousands of dollars.
As for the FFL issue, I think that as long as you're not getting robbed on the transfer it's not too much of a pain. Depends on how much you're saving on the gun itself. Paying for an FFL and keeping up with all the paperwork equals quite a few transfer fees.
Best
Nick
