Saw this over on Audizine. Guy picked up +80 AWHP with his APR stage 1 ECU upgrade and exhaust over stock with exhaust.
Power looks like it was still climbing rapidly but due to the DSG having a lower redline (6600 vs 7100) it shifts earlier.
His mod list says the following:
2011 S4 - Customized Milltek Non-Res, APR 93 ECU, Sprintbooster, KW V3's, 15%