I personally own and use the Marshall MG30 as my practice amp. I play with it my band, "The Haunt Of", which consists of Me on Guitar, a Bass Player (With a 4X10 Bass Cab), and an unmuted drummer.
Needless to say, it gets pretty loud in there.
But the MG30 takes care of it. I can honestly say that I generally have no trouble with it being too quiet, or anything like that.
And with the addition of the foot switch, it makes it perfect for playing with a band, and you could even Mic it to run through a PA for a live show.
Sound
I was really surprised with the sheer quality of the sound that comes out of this amp. I mean, for a solid state amp (No Tubes), you wouldn't expect such good quality.
You have a large amount of control of the amp as well. There are adjustments for:
Treble
Bass
Contour
Gain
Reverb
Delay
Chorus
Flanger
FX Mix
As you can see, there are quite a few effects to play with, and they all sound great.
For such a little, solid-state amp, it sure does pack a punch!
Ease Of Use/Feel
Overall the thing is really use friendly. If you want more treble, you turn up the treble. Less bass, turn down the bass. All very simple and straightforward.
My only complaint is, because it is a completely analog setup, some of the effects are not as precise as they would be on a digital display.
It's not that it doesn't do what you want, but because the knobs are all analog, when you are setting something that is as precise as Delay, it's not always at pinpoint as you might want it.
But if you aren't the type of person who cares about how many "MS" your delay takes, then you will be perfectly happy with the effects (I know I am).
And if you didn't fully understand that last paragraph, then it most definitely won't apply to you, and you have nothing to worry about.
Reliability
Very reliable.
The only problem I have ever had, was I once put a jack into the Audio, and it switched over, taking power away from the guitar in, which it is supposed to do.
But when I took it out, it got stuck switched over, and I didn't have any power.
Of course, after fiddling with it, the problem fixed itself and I never had that problem again.
This type of problem is quite common, and has less to do with the quality of the amp, and more to do with some of the jacks wearing out (Which could happen on any amplifier).
Other than that I have had no problems and would count on this amp in pretty much any situation.
Extra Notes
The foot switch that I bought for $30 really is a necessary addition. It makes playing with a band so much easier, because now I can switch between the two channels with ease.
Sometimes the switch gets a little stuck, if you hit it the wrong way. It's not a serious problem in the slightest, and has never cause me any grief, but I just want you to know that it isn't perfect (Although it is near indestructible).
Conclusion
This is a great amp. I recommend it for anyone who is looking for a step up from their 10 or 15 Watt Practice amp, but isn't quite ready for the big stuff yet.
PS: Click any of the images above to get more information on this Amp.