Both Vishnu Procede and Burgertuning JB4/JB3 are widely used in 135/335/535 (N54 and now N55) world. Both are relatively troubleless, have similar gains and are similarly easily installed/uninstalled. Both will probably void your warranty if car is brough to the dealer with tune inside. So, the key is - before dealers visit, remove it, get the BT scan tool and remove any tune related codes (if any).
I used JB products on my both 335i (2007 and 2010) without any problems.