Can anyone tell me if changing to high performance air filters will help with performance. Also, is there any performance software available for the V10 M6 engine
Yes different air filters can help but not that much like 1 to 2 hp. To really get a better effect on the air intake side you need a cold air intake. Cold air is more dense and promotes better combustion and more power from a good intake you can get 8 to 10 hp. There is software out there by many companies such as DINAN, ESS tuning to name a couple.
Like most all modern BMWs, your M6 already has a cold air intake including that it's inlet is in the high static pressure zone behind the grill in front of the car. The easiest change to make for a US model E6x M5/M6 is to remove the charcoal filters in the top of each airbox (main filter boxes). Here is a good write up on the procedure which is very easy: http://www.m5board.com/vbulletin/e6...coal-filter-removal-step-step-w-pictures.html See the M5board/M6board for vast quantities of further information.