Bet if you Mongoose owners actually bothered to measure the diameter of the pipe - you'd find it was 2.5in bore, the 3in bore will only come with a 4in inwardly rolled tailpipe - you have no choice in this

Magnex In my own opinion is the best for performance, the mongoose has the better sound and overall appeal to joe public

Given the chance, I'd have the Magnex front pipe and Mongoose fro that all the way back