Yeah, I see what you mean. However, I think it's safe to say that the performance gains will be similar to the G37. I think (hope?) that these will produce some nice gains when combined with a better flowing catback. It doesn't make much sense to do one without the other. Come on you're halfway there
Nah I understand where you are coming from, I'm thinking about buying a set myself and coupling it with a catless catback. I'll know sooner than later.