Yes I think this has been discussed but look at this other info I have found.
HKS Exhaust on the Tunersports.com website $556.70 shipped However its states it for the 2.2L Diesel engine.
HKS 31019-AZ007 Hi-Power Spec-L Exhaust for a Mazda Mazda3 « Free Shipping
But if you were to look at the this Mazda website for European accessories, it has a sports muffler that accommodates the following engines: 1.5L, 2.0L and the 2.2L Diesel.
Mazda3 Accessories
If you were to look at the Corksport website or Racingbeat their exhausts fit either the 2.0l or the 2.5l engines.
So, in theory, shouldn't all known exhausts work for all 3 engine options.
Look forward to your feedback.
HKS Exhaust on the Tunersports.com website $556.70 shipped However its states it for the 2.2L Diesel engine.
HKS 31019-AZ007 Hi-Power Spec-L Exhaust for a Mazda Mazda3 « Free Shipping


But if you were to look at the this Mazda website for European accessories, it has a sports muffler that accommodates the following engines: 1.5L, 2.0L and the 2.2L Diesel.
Mazda3 Accessories
If you were to look at the Corksport website or Racingbeat their exhausts fit either the 2.0l or the 2.5l engines.
So, in theory, shouldn't all known exhausts work for all 3 engine options.
Look forward to your feedback.