I’m looking for clarification regarding Mercedes-AMG models (2020+ model years) imported from Japan.

I’ve heard that Japanese-market AMG models may have a different exhaust setup compared to European versions, specifically:

• Louder / freer-flowing exhaust
  
• No OPF (Otto Particulate Filter) installed
  

Can anyone confirm if this is true?
Are Japanese-spec AMGs really OPF-free after 2020, and if so, which models and engines does this apply to?

Any firsthand experience, official documentation, or comparisons would be highly appreciated. Thanks!

I do not specifically know about Japanese-spec, but outside of the markets that require OPF, the 2019+ don't have OPF. For example that's the case with our US-spec versions here. Instead of the OPF, we have the same secondary cat setup as the 2018 and older had. AMG still reduced the pops & bangs on the 2019+ models in general. Something I personally don't mind as I find the senseless popping & banging childish. It still pops & bangs when the car is actually driven hard, such as when I hit up the canyons, but it doesn't pop around town for no reason annoying every bystander. I hate that myself when I'm out walking and one of them goes by. Especially if they modified the exhaust and the bang leaves a ring in my ears.