Came across Abaco MAFs while browsing some other forums. Looks like it could be useful for tuning DIY'ers.

http://www.abacoperformance.com/

I have zero experience with them but here's what I've summarized thus far:
It seems that the transfer function is digitally conditioned allowing the user to adapt it to a format digestible by a variety of ECU's - possibly saving You the trouble of trying to make the adaptations within the ECU. Feel free to study them in more detail & correct me if I'm wrong.

They're sold by Summit (just under $400), among other vendors.
http://www.summitracing.com/search/?keyword=abaco&dds=1

Have at it!

Regards,

H. Kurt Betton

P.S. The problem with ultimate adjustability is that everything ultimately needs to be adjusted.

I guess one could word it that way, but I see it more as a way to "recalibrate" the MAF for the specific combination of parts. If Your setup flows 400g/sec max, You can set that as Your upper limit (5v). 700g/sec? Set that as 5v. This gives the highest MAF resolution for Your setup since the full 0-5v (or whatever the exact voltage range ME7 allows) is being used - good for driveability.

I don't remember the exact constraints of ME7, but I remember some arguments about changing the upper limits of the MAF. Some people say, in addition to the MAF tables, 3 other tables need to be adjusted. Others say it's like 300 other tables, or some little quirky (safety?) algorithms will be lost. Regardless of who's right, the upper limits of these tables wouldn't need to be adjusted. Conversely, if one so desires for whatever reason, You could calibrate the MAF to some standard limit, and adjust the ME7 tables accordingly.

Regards,

Kurt