Hi New STIII owner, looking for advice

Hey this is my first forum, but im looking forward to getting some good advice from people with modified STIII's. I have a 2011 Street Triple R and I am looking into getting the arrow 3-1 exhaust and I have read that it is a good idea to pair it up with a SAI blockers, k&n air intake filter and a power comander? Im not to sure what SAI blockers do. Anyone out there have these mods on their bike? And does anyone have another full exhaust that is cheaper then the Arrow? alot of questions right off the bat, I'll take whatever answers I can get