Is a P0100 a common fault on a MY99 E300?

I've got a P0100, and think it's probably the MAF. Is there an easy test sequence to diagnose? I've looked at my CD, those diagnostics seem confusing. I'm temped to just replace it, since my research (and local parts store) seem to conclude they fail. (but they don't stock one)

And.... Is there a reason that the Merc MAF includes the round cylinder. It just seems odd. The electronics part of the maf more or less looks just like a Porsche Boxster one. (except my Merc MAF doesn't have a resistor, could the car have swallowed the resistor?) I think we need a little trial and error to try to find a cheaper solution, than a $300 dealer part. The local parts store is less. Mail order is almost reasonable. A friend of mine who works at Mack says, just drive it. But I can't do that. To me a CEL more or less means park it till you can fix it.