I notice the same binding or locking on my GST, I think it's just simple physics.. It's not horrible or anything but it's not liquid smooth, if you think about the nature of the brakes, metal to metal wouldn't necessarily be the smoothest material that comes to mind but it's more durable then those crappy Savage brakes that last a month =)

Correct me if I'm wrong as I haven't done this myself, but I would think you could just remove the metal brake discs and sand them smooth after a while and that would help un-groove them a little? I would ask around first though cause I could be full of it, sounds like a good idea to me though.