Im looking at changing my exhaust on my blobeye from the Prodrive one to a Hayward & Scott cat back and just wanted to know if there is much difference? From research it appears to have a deeper low down rumble but no drone like other exhausts. I do want more noise but not excessive amounts and this exhaust seems right up my street but you cant get a proper idea from the odd Youtube video i have found. Can anyone give some advice as to if its worth it?
They also claim 18 bhp from the upgrade but i assume that's with the second cat removed which mine doesn't have one due to the PPP but will it give some gains over the Prodrive one as i have heard its quite restrictive?

Thanks