I've bought a few guns from them. First was a DE 1911C that they got when I was interested in getting one. Decently priced under MSRP (at least for me). This was not long after they opened up in the first location.
I do know that they'll work with shops in MA for transfers (for pistols), so that's good. Store is on the small side, so not a ton of inventory. They also have some guns on commission, which means they're not setting those prices.
They'll also look up anything you're wanting to get that's not in store and give you a price without hassle.
I will say that the transfer fee is a bit on the high side for private sales. At least last time I checked.
I'd put them into the shops to visit rotation if I was looking for something and didn't want to spend time on the phone. There are other shops you can visit within a reasonable travel distance to compare and such.