The Marshall MG series aren't particularly well-liked around here. There're better-sounding alternatives around. Don't limit yourself to Marshall. Let your ears be the judge...
What kind of tones are you expecting from your amplifier? If you're looking for good cleans and slightly distorted clean tones, there's quite a variety of good clean amplifiers to choose from. The Sound Drive SG-10 combo I have has really nice cleans, as does the Vox Pathfinder 15R. The Marshall AVT series also sound pretty good at least to my ears, but they cost more than the Sound Drive and Vox.
For heavy distortion tones, get a nice distortion pedal. Majority of small-wattage amplifiers have weak, sub-par distortion tones. You could get a good clean amplifier, and get a distortion pedal to get your distortion tones.