I've emailed them for you, some of their staff are at the SEMA show so replies are a little delayed. I should have a response some time tomorrow for you.
Also Remus and Milltek are nothing alike either. Remus is much better quality for a start. If its good enough for major tuning houses like AMG, AC Schnitzer, Brabus, etc then its going to exceed your expectations on a SEAT. My boss has the Remus backboxes on his Passat W8, it sounds amazing now!