My poweramp option is using a 1U head, such as the GK MB series. If you can pick one up secondhand, it'll be lightweight and you have the option of using the preamp section on it too, or just plugging straight in to the return in the effects loop, that will plug you straight in to the power amp section. When I'm not using my Kilo head (i.e. a small gig) I'll plug my Ampeg BSP preamp in to th return of my GK MB800. The Ampeg BSP is a very particular distortion preamp and I am yet to find any pedal that sounds as good! but that's a bit off topic! - The point is, it sounds great using the GK power amp and makes a tiny rig too!