MRC do a replacement filter and pipe. Similar in appearance to AWE but significantly cheaper than that REVO link you posted..
Very slightly more charger noise but not enough to be a concern.
I'm interested to see how ditching the expensive Helmholtz resonators on the OEM air filter intake pipework adds to the supercharger whine / intake rush.
I'm going to test drive Revo's S5 in a couple of weeks to see what it's like so I'll do some sound recordings and post them up.
USP Motorsports do an induction kit for your S4. The carbonio induction kits don't get a good write up in the US as many owners have complained that they don't get any extra noise or gains. Not sure if K&N do an Typhoon kit for the S4 , but that's the kit I have ordered for my 2.0 TFSI, due to the excellent reviews about noise and gains.
Ave the Carbino intake pipe on my 2012 S4 V6T and K&N Direct replacement Cone Filter, And from inside the Car u don't notice much difference in Sound, but u notice a fair difference in the freeness to Rev, Not sure how it sounds from Outside under load.
The Carbino is Carbon fibre , very light and looks good under the Hood, Any after market induction Pipe that replaces the standard one will see gains, but to get the Charger wine louder u need to Replace the Airfilter box with a open Fillter design .... the standard filter in the S4 V6T is a large cone type
Kind of swaying towards the AWE kit now. Found a good video and whilst you can hear the supercharger its doesn't sound intrusive. Not sure about power gains but i'm sure there will be benefits and it has a more OE look
AWE Tuning Audi 3.0T S-FLO Intake System - Audi Performance - Make | AWE Tuning
Although bit of difference in price between black and the carbon version. The pipe also looks like a silicone pipe so could be susceptible to heat soak
Silicone hoses get hot, but nothing like as hot as metal. Yes they get hot, but then cool much quicker when they get cool air running through them again. I had a metal pipe running over the turbo housing and we had to build a heat shield and then wrap it as it was scorching hot. Silicone will never get so hot you can't touch it. The only way to cool the metal pipes sufficiently is a Zircotec or heat resistant coating, or heat reflective tape (e.g. Gold tape from Agriemach), but it adds cost. Metal pipes make more noise, so it's about finding the kit with the right balance of build to meet your needs.