To pick between the PS-100 (100 Watts) and PS-2 (50 Watts) you should be aware of the PS-100’s features in a live performance context; the differences are more than just output power.
The PS-100 has added features that make it very versatile for a live playing tool: think of the PS-100 as a two-channel foot-switchable power amp, that has independent volume and tone controls (presence and depth) for each channel.
The PS-100 also has foot-switchable FX loop.
For more information about that and creative use of the PS-100, watch Joe’s video,