Congrats! I love my GT150. One of the few amps whose clean tone is so huge I don't miss reverb.
The GT150 is a single channel model, and I have used the amps own gain at times finding it quite good for all things short of tight brutal metal tones. But for flexibility I prefer setting it as a clean amp, and using a treble booster, OD, fuzz, or distortion pedal for my dirty tones. It gobbles up drive pedals like John Pinette at a Chinese Buffet. The one exception was my RAT. The RAT's filter did not play nice with the EQ section. Not sure if it was the Depth knob, or Baxandall EQ section, but it neutered the amp.