Version 1 used non CCM compatible guide rod sizes so it was sold as an entire pump kit tjd10684's Carbon Fiber Pump Kit
This is the version1 kit but the outside geometry of the V2 is almost exactly the same. I have not had any issues with it slipping but it might be my technique I tend to keep my index finger over the front of the handle.
I did not do any respringing to use it it seams to work well. I think it returns quicker since it does not take as much to get it returning. BUT it does jump a little more when you shoot. its kinda 6 one way half a dozen the other.
I think the main advantage is it really helps the weight distribution and makes the gun easier to hold in shooting position longer.