I will soon be in the market for a performance ecu for my 850 t5r. I have looked at many different chips and would like to know if anyone has any of these ecus on their 850? The two chips I am seriously looking at are the ipd motronic chip($900) or the PES chip ($650). The ipd chip claims a 35 hp increase with an exhaust, while the PES claims a hp increase of 40, with no mention of an exhaust. My only concerns are that some of these companies require that you send in your old chip to have it reprogrammed or whatever, this is something I would like to avoid, simply because I really can't be without my car for long because I have to go to school and work, etc. Does ipd need your old chip, or do they just send you a new one to put in yourself? Same for PES? If anyone has had any experience with these chips or others that you would recommend I would greatly appreciate it. Thanks.