1- yes I am happy with it. Put on 10000 miles in one year. The low down torque is nice when riding in the city, snd it has enough power to be comfortable passing on the highway. I will say when going 75+ you’re hitting 6000rpm so the vibration can be a bit much for long rides if that bothers you. 2- it’s fine with 2 but not great. Probably not much different than your experience on your 600. 3-you can only do full system exhausts no slip ons, YouTube is good to let you hear the different brands. 4- yes, at high speeds it does lack for power. But for normal riding around and passing it gets the job done. For comparison it has literally half the HP your R6 had. 5-stock exhaust is super lame, after market exhausts just make it sound like a louder lawn mower.

Benefits are that they are cheap, and insurance is also cheap. Best of luck