I've come to the conclusion that two brothers does not make a full exhaust system for a CBR 954

 

I got my bike with a yoshi on it. just received the two brothers black series that i ordered. it looks and sounds better. i hope that the tone will deepen once i ride it some more, ive only put on a couple of miles on it so far..

 

Yoshimura does extensive R&D. They have developed their own CAD program to design and they make all their materials in-house and they've got a couple in-house dynos as well. Every pipe they make is tested and if it doesn't improve performance, the design is thrown out.

Two Brothers is a company formed from the ashes of Erion Racing. Remember those brothers who built race winning Hondas? I don't know much about their whole process of R&D, but they know what they're doing.

You're not gonna go wrong with either pipe. I'm gonna have to say Yoshimuras offer a bit better in terms of build quality and I deeply dislike the way the 2Bros "carbon" looks like a cheap look a like sticker, but both companies know what they're doing. Both companies offer great customer service. I know with Yoshimura you can send in your pipe if it's ever damaged to get fixed, I'm sure 2Bros offers a similar service, but I'd check with them if that might be of concern to you.