At 72k miles they may be due for replacement, but may also be fine; try the fuel flow test and see what numbers you get.
I'm at a tad under 190,000 miles; I replaced the original MAFs at around 80-90k and noticed some improvement. Cutting a long story short, I had a brief experience (10-20k miles) with VW MAFs that I thought were originals and they made my car sluggish. I spent quite a while trying to work out what was wrong before I took the MAFs out and noticed the different part number. I put original set number two back in (they now have around 90-100k on them) and the car is still performing well; it pulls around 140-145 L/H on the fuel flow test.
I see the post about them and Bimmerzone has the pair for like $345 which seems very good. Trying to get a grasp of what I can expect to do on the M5 I should be getting this week. Seems like the MAF are due for replacement at some point in the near future as well as Spark plugs.
Trying to read up and get as much info as I can. Will find out by Wednesday if I am getting the car.