Alot of guys in the comments on youtube preferred the m55. For me it's a matter of taste. Where it gets more subjective is what amps you pairr certain speakers with. Anything brite or harsh or dark sounding won't pair well with a Quick Rod. But there are guys out there that like v30's with their QR!!That is pretty much what I'm experiencing between my Creamback cab vs. the Blackback Cab (basically a 25 watt GB, just different colored plastic). The CB is just a little more "edgey" and brighter sounding.
As far as this comparison goes.. There is no comparison, the GB kills that Scumback IMHO. But, where are you going to find a quad of Pre-Rola GB's without dropping some serious coinage.. LOL