Haven't bought anything from there, BUT I did Email one of the sellers that was local to me and asked about buying from him face to face, and he agreed to do that, and I happen to mention that I would/could take him out to shoot some prairie dogs, if he was interested, and asked that he might concider that when setting his asking price. Best dang move I've made in a long time. Not only did he work with me on the price, after taking him out the first time, he's now selling primers and powder to me at the price he paid for the stuff.
Moral of my story, if there is a local seller to you selling what you want, don't be shy about Emailing them and asking them if they would be willing to work with you on the price. It might pay off in the long run. There are some "crooks" on Gunbroker, but I found out that there are some guys that are willing to work with you too. Crooks, as in asking way to dang much for what they're selling. Price gouging, in other words. I've seen Rem 7.5 primers at asking price of about $100/1000, including shipping price. That's highway robbery!
Good luck!!