I purchased the amp as I needed a small tube one for home practice and occasional rehearsals. A 20W pure tube is more than enough for that - it can easily power a 2x12 cab while keeping some headroom.
The G20, through a V30 speaker cab, sounds rather american/modern, although the morph knob allows you to colorise the sound to give it a more british tone if you're into marshall amps (it's not a real brit of course but it gets that certain feel when turned to 11;)
You can get pretty decent distortion out of the box and nice metal sounds when running a TS in front of it. It's not a dual rectifier type of sound though - if you want to melt the paint off the walls get a Mesa or a Peavey instead.
Cleans are nice but not using them much to be honest to give you the full picture.
Things I really like on that amp:
- Headphone out working in standby mode and builtin speaker simulation
- Speaker output with switchable resistance, you can hook this baby up into virtually any cab out there
- Good build quality
- Sounds nice, not spectacular but I'm happy with the sounds I can get out of it
Things to nitpick about / would be nice to have:
- Headphone output with a forced speaker simulation, would be nice to have a 'clean' one there
- A separate EQ for the clean channel would be awesome
- For my taste, 12AX7 preamp tubes would make this thing slightly better