Quality:
I have used these speakers for five yea\rs and a awful lot of gigs, no problem at all.

Value:
Good value if they are the right match for you style.

Desirability:
Sorry nothing sexy about a speaker...maybe im wierd!!

Sound:
I have used various Marshall "vintage amps through my Marshall greenbacked 4x12" A reissue 100 watt superlead plexi,DSL 2000 50 watt,a 79'JmP master lead 100 watt and even a 63' blackface bassman head. I play in a Hendrix tribute band and am constantly trying to improve "my sound" much the same as zillions of other guitar players. I find the combination of Marshall amps with this particular speaker cab and a strat to be lacking in mids, somewhat bass heavy and at times quite shrill. Having used other 4x12"s with celestion G12s and the vintage 30 I find I can achieve a more balanced sound, however I miss the early speaker breakup of the lower powered Greenbacks.I was thiking of changing the greenbacks for vintage 30's until I recently bought a Marshall jtm 45 Reissue..WOW! in my opinion they are a match made in heaven! I believe my problem was using a high powered amp and relying on speaker breakup, whereas with the lower powered JTM 45 it breaks up earlier(being only around 30 watts) I am now a happy man. I have talked to other guitar players who swear by the greenbacks, even one who uses them with a Boogie single rectifier head, so as the old saying goes "Suck it and see" try as many speakers with your own amp as possible, preferably in a live band situation. Don't listen to anyone, listen to your ears, and if it sounds good to you, go for it. You will save a lot of time and money if you do.

Overall:
I expect to use these speakers a long while yet.