Re: Marshall MG250DFX
First, try it out if possible, WITH the guitar you will use (or very close to it).
The MG are good for some music but not everything, I own the head version by the way.
If you are really planning on moving it around a lot, why not try the MG100 DFX instead? it'll probably be a lot more moving friendly and it'll almost sound the same. Also, It'll be more apartment friendly since even at low volumes 2x12's might cause enough vibration for the neighbors to hear you play, can't say that for certain though.
Being solid state it'll naturally be ok at low volumes and its pretty good at high volumes...it really does get loud! Especially for a solid state amp.
All that said, I find it really helps to have a good overdrive pedal with these amps.
If you want something else, look into getting an Epipohne valve Jr, a good pedal or two suited for your style, and a 12" speaker cab. Depending on what you want and what you like this May or may not be better. It's a tube 5 watter, getts pretty loud though.