HobbyTron is a really bad retailer. I've had nothing but wonderful experiances with www.airsoftatlanta.com www.poweredgeusa.com www.airsoftextreme.com www.airgundepot.com
KWA is considered by many these days to be the cream of the crop. They have a large assortment of GBB Pistols to choose from and have an actual manufacturer's warranty.
Tokyo Marui makes excellent GBB Pistols as well BUT are too expensive for what you get these days.