Dante,
It sounds like you converted it from a work horse to party animal! You should have kept it at that point.
I know what you mean, and it's true, you do have to change the way you work the synth for certain instruments. I knew that going in. I'll figure out how to do what I need to get the textures I want.
The GP-10 has a harmonica in it. I don't have a use for it just yet, but I'm just getting into it. So far, some of the useful non-guitar sounds in it are Synth Bass, Dual Sync, GR-300, (which you can play chords with), Sequencer Tap & Hold, Synth Pedal Blend, Clean Bass, Slow Pad Filter, Hyper Wah, Synched Sequencer, Oscillating Crystal, Crystal Bell, Soft Brass, Chorus Strings, Synth Mix Solo, Strings, Expression Pedal Follower, Rotary Crystal, Fretless Bass, and the Heavy Funk Drive.
Three of these I listed have modeled guitar mixed in with the synth effects, and several of the others I didn't mention also have that, but the synth sounds are so far in the background, you barely hear it. In most cases, I'm not interested in the modeled guitars it offers. Then this also offers a wide variety of guitar oriented effects, but half of them don't use your actual guitar pickups. There are some patches that do use your guitar and you can set up your effects chain the way you want it, (I think), so that could be useful for using this as a stand alone fly rig.
Overall, if I had to rate this pedal at this early stage, I would say there's about 40% of the things I hear that I can actually use as a guitar player. If I have a gig where I can't use an amp, and have to go into the mixing desk, this could be a very good tool for that if I edit it correctly. As a fly rig, If I go to Best Buys, and get a small zipper case for it and its cables, I can put it in the glove box of my car or truck, and go. That's pretty cool.
So far, that's all I can say at the moment. I've been having fun with it though. The manual is rather brief on each topic, but it may be enough to guide me through it. I'm counting on my experience with multiple signal processors to be able to figure out editing parameters in this. I'll be posting more on this GP-10 as I gain a bit more experience with it.
When I get any of the other Roland guitar synth modules, I'll probably post them in this thread rather than start a new one.