Originally Posted by NeverEnough
I've got glasses........
This isn't what I would consider a "key" component. Unless you are going to be running a stand alone EMS, and doing serious tuning on a regular basis (hard to do without a Mercedes diag computer or EMS) these aren't that necessary. For $500, I can think of other things I'd rather have. But that's just me. It is a clean setup and the datalogging would be nice, although of limited use to me.
To each his own. I've been around modified boosted cars for years and have seen many blown engines due to leaning out. Most of those were due to ignorance by not having A/F monitoring capabilities or people cheaping out and getting some Autometer narrowband gauge that doesn't accurately warn you of dangerous conditions. If you're stock and just want something flashy to stare at then by all means get some $100 or less gauge. If you plan on doing lots of mods(and making your own) it is best to have something very accurate that can store critical data.