Definitely some shots fired across the starboard bow.
Wow, this thread is a one fascinating read.
I heard about the whole RSC story and started reading only a few days ago. These are some horrible business practices and unprofessionalism described here and supported with evidence. I only wish there was a more detailed summary or FAQ on this for people who are new to Audi modding community. More people should know about this, I’ve been reading Audi forums for about a year after I got my S5 and didn’t see mentions of the topic on AZ or AW until I stumbled into a post mentioning “RSC controversy” and looked it up. Also have never heard of AudiRevolution before, looks like a great place.
I guess I am a great example of how effective APR marketing is.
I got my car August 2014 from a dealer where it was on sale for a while, because it had an absolutely retarded loud custom exhaust. It’s a fully loaded 2015 S5 4.2 auto with Audi care and some extras. They originally put it on sale for 48K, nobody wanted to buy it, they kept dropping the price and after watching it for a while and some bargaining for an extra discount to replace the exhaust I got it for 39K and traded my old A4 in, so S5 was my only car. Driving it with that loud custom exhaust was simply unbearable, previous owner for sure either was deaf or became one as a result. I didn’t expect to actually buy this car so I didn’t research exhausts in advance. I quickly looked up what’s available and was choosing between “big names”: AWE and APR.
I picked APR because of their claims of no drone, effective sound cancellation and being quieter than competitors. I was able to find it on discount for 2300, while AWE Touring with resonated downpipes was close to 3000.
It indeed does not drone and the sound is quite nice, very quiet inside at cruise and gets angry at WOT. I have no clue if it’s any quieter than AWE or other competitors, on AZ there are comparison videos for S4, where S4 version is indeed a tiny bit quieter. I did not dyno the car before or after and didn’t run a quarter, so I have no idea if it gives any gains compared to stock. Butt dyno says that it’s miles better than the custom crap that came with the car, I’m sure though it’s because that system was utter crap.
I now feel somewhat ripped off because I bought RSC exhaust, very uncertain about the quality of welds and corrosion resistance, need to inspect if on a lift or jack stands. If I knew about this whole story I would have bought AWE or looked for something else.
I looked inside the exhaust pipe, and it’s a straight-through with a round/oval cut out in pipe leading to a muffler and a small perforated section closer to the end of the pipe. Looks a lot like what AWE describe in their design.
Did anyone see pictures of 4.2L S5 RSC exhaust cut open? If not I might get a borescope and try to see what’s inside.
S5s that are 2013 model year (north america) as well as all cabriolets no longer had the 4.2 V8 (you mention that you have a “2015 S5 4.2”). They now have the 3.0V6T supercharged engine.
For what it’s worth, I really liked my APR RSC exhaust when I had a 2011 S4.
And welcome to AR! 
;D
Well spotted, that’s a typo, it’s 2012, not 2015
Welcome. If you could get a borroscope shot that would be cool. While they RSC part of the technology seems to be a lie, if it doesn’t drone then at least they hit on half of their claim. A few of my friends had APR on their Golf R’s and have since switched. Not sure about the S5 exhaust but they all had problems with cracks around the welds to the muffler.