Mine on an 07 Bob has been a mess - performance gains not noticable but fuel consumption has gone through the roof, the idle isn't stable anymore and the speedo needle jumps around. Not sure what to do.
I installed the Cobra on my 07 RG. Easy to install and works great. It dropped engine temps , smoothed out the idle,and gave my RG a strong kick . No problems with the unit since install 8K miles ago.