I buy from copper/hy when they have good deals. I don't have them do any tech work, I buy it bone stock and send it elsewhere for alignment/tuning/mods. Maybe if they posted a picture of their bench and test equipment, and posted the tech who does the work's credentials, I'd be more comfortable about it. But they've never approved any posts in which I've tried to ask for details about this. They are evasive about it.
I will definitely try quackshack next time I want a radio. I have heard nothing but glowing reports about them, that's all I need to hear. They have a good forum, too.