I put one on my 2009 FLHTC. It handle the Install of the stage 1 K/N AC good, and it handled the Super Trapp 2 into 1 well. But when I installed a set of Andrews 48H cams it failed miserably. It can't adjust timing.
I had one on my 1996 FLHRI and it worked well. I had previously been using a DFO but couldn't tune out a "flat spot" it had when trying to pass at freeway speeds. After putting the Cobra on no more flat spot, just increased acceleration.