Best oil for a '99 M3 with 80k miles

[rlme36]

I have a 95 M3 with 66k on the clock. I do track the car, but only drive it in the warm weather. Last year I used Amsoil 10w-40 for the first time and did an UOA and was impressed with the results. I posted them on the UOA forum. I found this oil thick enough for the tracks that I go to in the NE in the summer. I have toyed with the idea of getting their TRO as its supposed to be excellent, but that would be over kill for your intended application.