I have done lots of reading on here regarding the TWS recommended for the M3s and M5s. I just want some opinions on running Shell Rotella T4 15w40 in the S54. The car sees cold starts normally anywhere from 40-80 degree F weather. It is a day to day driver and it doesn't get pushed hard when oil temps are low, if ever. 6 speed manual. I am wanting to run a quality conventional oil in the car for a few OCIs. I have always liked this oil and I have lots of it on hand. I understand that not running 1060 in these cars is treason. I get that. Any educated opinions? Bear in mind this car has 200k miles on it, has had the rod bearings replaced and I have $4 grand in it. Thanks for the input.