DiabhailGadhar, email inbound, we'd like to replace your BAD-ASS 90 degree center with the current production unit. Back in Feb. of 2012, there were some in the batch that were harder to rotate, the new centers incorporate all the improvements we've made since 2010

They have improved detent groove depth, shoulder, angle and holes, the result is a smooth rotating selector without being mushy (which some users mentioned, as the first generation of BAD-ASS centers had a deeper detent groove), and positive detent engagement.
RE: BAD-ASS vs. BAD-CASS, we posted the info here
https://www.m4carbine.net/showthread.php?t=112484
Info on the 45 degree selector can be found here
https://www.m4carbine.net/showthread.php?t=82851
About the levers, almost all of the LE agency purchases have been equipped with standard (left side) and short (right side) levers, this configuration happens to be the most popular, and most usable for the majority of users. If you'd like to try other levers, we have a free lever exchange program just for that, so your choice in levers isn't final at the time of purchase.
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