you rang?
Depends what you want it for really.
[b][u]GK[/u][/b]
+ Great tone, very flexible, separate tweeter and bass section amps, so useful if you use the GK cabs. Well made, crazy powerful!
- Weighty (compared to the GB)
[b][u]GB[/u][/b]
+ Well made, all controls you'd ever really need. TEENSY TINY. Powerful enough for any gig really as long as you use an efficient enough cab
- Tone is very good but not great. Not as much of a range of sounds.
Basically the GK is better tonewise (IMO) but a big bastard, but no bigger than other MOSFET amps of that power. If you can take a slight tonal inflexibility and value portability highly then I'd choose the GB (that's what I did )