MG15, 30 and 100 were decent solid state amps except for the shotty electrics (from India I think) hence the bad reviews but sound was very good for the price you paid. Nice old school grunge was what they were known for and decent clean with some extra simple effects (delay, reverb etc) just to play with. Remember it was marshall's entry level amps - so in terms of tube modelling was pretty average.
Some got lucky and had no reliability issues others didn't. That's why it was a hit and miss and poor reliability review. I was part of the first lot for first 2 years where it worked fantastic..then 3 years of no use I decided to turn it on...
Great modding platform - celestion maybe, eminence, or ram-rod 10" speakers for the british crunch. Beginner's amp definitely not tube