I also have one of these equipped in my hop up arsenal for testing - you'll notice the curve in the nub unlike the prommy bridge or flat nubs.
The sleeve is also very similar to the PDI-W Hold - same contact points, although a very noticible difference in actually sleeve length.
Edit: Although with any flat nub i've tried (Prometheus, X High-Tech) like the SCS, all of my adjusment arms have never been able to engage well enough when the mound is shaved off.
