V1: takes Spyder threaded barrels; exposed solenoid on rear of marker; exhaust port on left side of marker; spool valve cover on top of marker; no sight rail; no circuit board; ss braided hose from regulator to body.
V2: takes Autococker threaded barrels; enclosed solenoid on rear of marker; exhaust port on top of marker, spool valve cover on right side of marker; sight rail; simple circuit board; hi-flow fittings and hose from regulator to body.
The body styling is different between the two versions; both at the front of the marker and at the rear of the marker. Since the V1 did not use any circuitry, the solenoid was energized as long as you held your finger on the trigger. This could lead to short stroking if not careful. The V2 used circuitry to help time the marker, but is known for its shot buffer and questionable timing issues. Not entirely positive, but the internals should be interchangeable otherwise.
Not really similar to the Nova design, but uses some of the same general ideas of course.