Today I installed Racesengs full pulley kit. Everything fit perfect and no dramas.
So benefits agains of less rotational mass and oh yes they look great.
Didnt notice any noise at all on mine to be honest and well I'm damned picky about that kind of stuff drive around for half hour after install with radio off etc to really pay attention nothing concerning was heard. So...either I'm going deaf or there's no noise as my car is pretty quiet setup overall.
Took me maybe 40-45 minutes to do install and being carefull etc and I'm no mechanic so pretty simple.
REALLY hoping Raceseng does the covers they sneak peaked on FB those look like a very very nice compliment to the pulleys.