Gotten this because my previous Fujitsubo Giken Legalis R noise annoyed me like hell. To my surprise as well. One thing i've discover almost all aftermarket exhaust available for 4age 20v from Japan comes with 2.38inlet size. Here there are no pipe with that size.I see that you have two midbox. One larger and one smaller. Mine is similar now. Just that they are not branded. Two medium sized midbox. I guess branded ones are really worlds apart huh? Silent, good fuel consumption and increase power all in one package? A bit too good to be true. But once and for all, I am going to try to get a branded 4-2-1 extractor hopefully some time mid year. Want to feel that mysterious all round good effects.