HP Tuners for a Mixed Fleet – Chevy, Ford, Mercedes, Infiniti, Dodge – Worth It?

I’m trying to decide on a main tuning tool that can handle my mixed garage:

• Multiple Chevy (LS/LT platforms, trucks, etc.)
• Ford (gas and possibly diesel)
• Mercedes (modern models)
• Infiniti (Nissan/Infiniti platforms)
• Dodge (gas and Cummins diesel)

I’ve been looking at the HP Tuners MPVI4 + VCM Suite because it has strong coverage for GM, good Ford support (including newer models and recent EEC-V additions), and some Chrysler/Dodge vehicles. It also has limited but growing support for certain Nissan/Infiniti models.

A few things I’m wondering about:

1. For those running a similar mixed fleet — is HP Tuners your main tool, or do you still need separate bench tools (like KESS3, Autotuner, or WinOLS) for the Mercedes and Infiniti side?
2. How well does the MPVI4 handle newer Ford and Dodge/Chrysler vehicles in real-world use? Any limitations you’ve hit?
3. For Mercedes — do most people just send it to a pro tuner, or is there decent OBD DIY capability with HP Tuners on certain models?
4. What extra gear do you pair with it (wideband O2, etc.) for good data logging and tuning?
5. Overall — is the credit system and MPVI4 worth the investment if you have 5+ different brands in the garage?

Drop your experiences, wins, frustrations, or recommendations. I’ll update this thread once I make a decision and start logging some data.

Looking forward to real garage talk — no fluff, just useful info from actual builders and tuners.

— David | What’s In Your Garage