After watching some videos of LambChopper678 who uses a DSL20 to recreate the sounds of Metallica, Death, Megadeth and so on, I bought this amp. And so far I'm quite happy with it, it gives a very good impression in quality and the sound is amazing.
However I wasn't aware how loud 20/10 Watts are, so most of the time I use the 10 Watt setting and the volume at 2 o'clock. In retrospective I would buy the DSL10, just because I don't want my neighbors to hate me.
Anyway the sound is amazing and can really sound like some of the bands mentioned above. So overall I'm really enjoying this amp.