The base clamps on the 6004 are one of the best in the industry. The string clamps can be replaced with other similar clamps. I have three sets of string clamps for my 6004.
Gamma Cusomter Support is one of the best. With Prince you will need to deal with Tennis Machines, the authorized Prince repair center.
The Prince NEOS 1500 is more comparable to the Gamm 6004.
Machines: Gamma 6004 2-point w/ Wise 2086 & Babolat Sensor Dual