I had my AFN up to 150bhp and 245Lb/ft with european 130 injectors and digital tuning box.
If you want info on the tuning capability of the AFN you should talk to Simon Cooper of Central VW Audi in Ellesmere Port. He decided to test to destruction the 1.9TDi in his Mk2 Golf and got a reliable 350+Lb/ft before his next stage of tune confirmed what he thought as it bent the rods.
http://www.centralvwaudi.com/aboutus.htm