Call me crazy, but I just put in WallMart Super Tech 5w-30 synthetic in my 94 325i with 63,000 on the clock. just bought it when it had 61,000 and don't know what oil was used but seems it was always serviced at a BMW dealer. Have used Super tech oils for some time, in hard driven snowmobiles and a WRX Suberu etc. with very good results. These oils meet the highest BIA (for 2 cycle oils) and API SF rating etc. SINCE BMW now says 5w-30 is good, why not ? Actually Super Tech is from Penzoil, maybe not a Mobil one , but not an off brand either. The Subie engine with turbo and 230 hp is certainly higher stressed than the BMW naturally asperated 6 so I can't believe there will be a problem. If so will let you know, if not will spend the substaintial savings on other fun goodies !