CH - have the SERT on my 02 RK & my 07 SEULTRA. Do not know much about the Super SERT except it is from a different manufacturer.
I would check with you dealer on any warranty issues involved - my dealer said there would not be any issues with the SERT as long as they did the work. If somebody else did the work & something screws up, then it gets subjective. Others here do their own SERT stuff - more power to them (pun unintended).
SERT allows each cylinder to be tuned individually, and to do this best, the bike needs to be dynoed. It also allows for a negligible drop in gas mileage with a very noticeable rise in HP & TQ. Had mine tuned after the 1,000 mile break in & was very happy with the results all around.
Others prefer other products = Power Commander, Fuel Pak. Best advice is whoever tunes your bike - use the product they recommend/like best. They know what gives them the best results, and the tuner is more important than the product, basically.