Originally Posted by AM03GT

VSC2 is a good upgrade. Personally I used them on my TC5 for the 2 years I ran it I only rebuilt them when I wanted to change the weight of the oil for tuning. I never leaked and they never changed from the day I built them. The advantages over the standard VCS is that with the upgrade you will have a bladder shock which is easier to build consistently and if you like zero-rebound (i do) you can get that with this upgrade. Also you don't have the time wear and tear of the VCS foam.

VCS3 does not have an upgrade because it is a completely different design. The body is new accepting a single o-ring with spacers and the seal is bottom loaded with an aluminum cap versus the top load friction plug of the VCS and VCS2. "Upgrading" to the VCS3 from a regular VCS does not retain any re-usable parts except for the ball cup.