The nice thing about McCruise, is the lead engineer for the project used to work on the Australian F-111 program, and has that philosophy for the cruise control.
It is fully integrated, with illustrated step-by-step instructions in the best traditions of such similar to the Haynes manuals of old that were based on actual disassembly of real vehicles.
So yes, the kit is involved, thanks to all the functions -- there are safety disconnect functions for clutch and brake - there is the speed sensor tapped off the ecu, there is an actuator that must be inserted in line with the throttle cable, there is the user interface, and power, and maybe something else.
On the Rocket, being a mostly open bike, it's straightforward, and it really works.
And
@barbagris has a misconception. Just because one has cruise control does NOT mean constant speed. I find myself often bumping the cruise control up and down for whatever. Having the ability to relax one's right hand makes all-day riding possible for me.