On-Board Diagnostics (OBD) scanner tools for MBZs... & VWs too!

[Samuel M. Ross]

I'm in the midst of doing two things:
(1) Learning about the history of and the current state of these diagnostic tools... this in order to
(2) purchase a scanner... probably a mid-to-low end model that will do basic scans and reset check engine lights etc... AND I would like it to work for both MBZ(s) and VW(s).

Yes, I have done my homework... searching and studying a bunch of THREADs/POSTs on this WebSite... including Steve Brotherton's POST in 2004 at:
Diagnostic tools for the 38 pin diagnostic connector .
and my studies have also led me to reading various model scanner's "Users' Manuals" to see what, if anything, they say that specifically pertains to MBZ(s) and VW(s)... but thus far there has almost been very little to nothing.

I know that 1996 was the official start date for the official standardization to the OBD2 specification and I presume before that date the DIYer is likely to run into a need of special connectors/adapters to be able to connect to some of these earlier models during the period before the standardization that OBD2 brought to the industry.

Right now I think I have a need to perform some kind of " RESET " on a 1995 VW Jetta III GL on which I just replaced the airbag "spiral spring" following the procedures in the $50 Bently manual procedures. Bently implies that the airbag controller [aka "computer" ] automatically resets but local shops that specialize in European cars say otherwise... and of course the VW Dealers want ~$300 to perform a check and reset!

Does anyone out there have direct firsthand experience with OBD while working on MBZs and/or VWs... and do you have any advice in general on OBD type scanner tools that work well for these cars and specifically my airbag situation?