my friend has a mugen catback and hes worked with different car parts and fabrication himself. the mugen exhaust is the BEST quality exhaust you can get for your honda/acura.
the welding style that mugen uses is way better than all the other afternmarket ones. i think they use "tig" welding vs. other companies that use an easier style of weld. Tig welds take much longer to do and result in a much stronger and high quality weld.
yes, it is really expensive and i would probably take an alternative cuz i dont have that kind of money to burn, but it is high quality. depends on how much u have to spend and how far u're gonna take it.