Didn't realize that Dextros wasn't pure synthetic. How does it differ from Mobil 1?
Being retired, I'm not a high mileage guy (less than 5K/yr) , so with my 2002 325i (traded for '13 ATS Lux) and 2005 Z4 I changed my oil (and filter) annually with Mobil 1. And, as far as I can tell (no analysis), the 325 at 65K miles and the Z4 at 40K miles, have always been running perfectly with no indications of oil related problems.
Being retired, I'm not a high mileage guy (less than 5K/yr) , so with my 2002 325i (traded for '13 ATS Lux) and 2005 Z4 I changed my oil (and filter) annually with Mobil 1. And, as far as I can tell (no analysis), the 325 at 65K miles and the Z4 at 40K miles, have always been running perfectly with no indications of oil related problems.