A lot of people don't like the metal zone and say all kinds of bad things about it but I think it can be usefull. You can get a huge range of sounds from it, the eq controls have a lot of range in them. Of course it depends what you hope to acheive. I'm not normaly hoping to get a 'nice' sound when I choose to use the Metal Zone haha. It has quite a harsh distortion sound. If you are looking for a warmer more natural (amp-like) tone then the RAT is a good, cheap alternative. You might want to try 'boosting' your distortion tone with an overdrive or distortion pedal, that sometimes gets good results as it keeps much of the fullness of the amp sound.