Had AJ do the rear bushing, made a helluva diference in the ass hop issue.
Broke her lose in 1, 2, and 3 just to test it out, silky smooth ass wiggle, no hop.
I would take the CTS-V over the STS-V, The sts-V has the 4.4 S/C Northstar, the CTS-V runs LSx engines (04-05 N/A LS6, 06-07 N/A LS2, 09 CTS-V has a S/C LS9)
Seems to me the aftermarket on the LSx engines is a wee bit stronger.