Quote Originally Posted by Caleditor View Post
... SD calibration lack a lot. It would take me hours to explain everything that the MAF is a function of ...
Trying to answer the OP's questions about a COS ... not interested in a Coke vs Pepsi debate regarding SD vs MAF tunes. You will find very knowledge people will that will line up on either side of that fence. I work with mainly E38 / E67 these days ... a lot of folks seem to want an A6 in their dream car.

MAF tunes are prevalent for several reasons - they are quick and easy (meaning they cost less), they require less knowledge / experience on the part of the person doing the tune, and only EFILive has these (E38 / E67) VE or VVE tables native within the tuning software.

Having driven and tuned a lot of these, the SD tunes (or SD and MAF combined) always seem a little crisper during rapid throttle transitions, than do the MAF only tunes - but perhaps this is merely my person bias.