We just started dealing with CCMG and I have to say they are some of the nicest folks around. Not only that they have superb guns and products at pretty good prices. Check them out and check out the cool videos of a Beta Mag dump.
http://www.cmmginc.com/vids/Beta_Dump_M2.mpg
http://www.cmmginc.com/vids/Beta_Dump_MP5A2.mpg
http://www.cmmginc.com/vids/Beta_Dump_M2.mpg
http://www.cmmginc.com/vids/Beta_Dump_MP5A2.mpg