They will be custom two of two made based on the Dynomax ultra flo straight through designs except that they will be in aluminum. Trying to keep this pup semi-quiet on the streets. Maybe he will make them as a limited series to sell to other cats as well.
They are a little hefty on the wallet, but some people have paid more for stainless muffs that are really heavy on the wallet aside from the chassis.
There are other alternatives out there but I'm going for every bit that I can. The bullet Vibrant's are super light, but may not muffle enough to drive the streets.
On the note of mufflers, consideration should be taken when designing the muffler body itself since there is a lot of air streaking under the chassis. The more aerodynamic the muff, the better.