I'll try to get some pics over the weekend. I would have got them at the time but the work was done by a friend while it was being repaired at his garage. A3Tom, I believe the holes on mine are on the right-hand (when viewed from the front) side of the airbox and underneath. This keeps the warm air pulled through to a minimum as the right-hand side is where the intake points anyway, and by drilling underneath you can take advantage of the air flowing above the gearbox.
As Fran said, the noise isn't offensive or silly, just lets you hear the turbo spooling and you get a lot more re-circ noise. In fact trying to get the car to produce different sounds is quite addictive. You also get a much more prominent growl under load. If I can I'll try to get some clips up over the weekend too. I have some of the car before the airbox mods, so it will be interesting to compare.
The MAF screens are a doddle to remove, you can literally pop them off by hand. I am aware of Ess_Three's reputation on here, and to be honest if I had read his comments regarding his MAF failure before I removed my screens I would have probably bottled it, considering the wealth of knowledge he possesses on all things S3. But it's done now, and the difference is so pronounced I don't think I could revert back to the old set-up even if I wanted to. I'll just have to wait and see if his MAF failure is replicated on mine or if it'll be okay.
Also, I don't know if it makes any difference at all but mine is a BAM, I thought it was literally just a software update but someone told me the newer engines are slightly different (some kind of variable valve timing or something similar) so I wondered if there may also be subtle differences to the intake system / MAF?