I'm a huge fan of the idea, and I love my Lifeson LP Axcess. I have never tried Parker's version, but I've heard that they are very good too--there are others out there, so let me know which ones you like.
My Ghost system is voiced darker than most but it has plenty of top end,and it works great through a clean amp like a Vox AC15/30. I'll stop there, but I could talk all day about the tonal possibilities.
What I really wanted to share is how I have mine set up for live gigging. I use my Pod HD500, effects only, and run the humbucker output into the guitar input on the Pod. The piezo output goes into the Pod's Aux input. I keep the signals completely separate by panning the mixer hard left/right. Each pickup gets its own set of effects and is then routed into either an electric amp or an acoustic amp.
The volume pedal effects only the humbuckers, so it works like a blend control with the piezo engaged. The piezo has a push/pull volume on the guitar to engage/disengage. I have a lot of control over the system and more importantly, it sounds fantastic. Here are my Pod settings:
The top row has the effects for the electric humbuckers. The bottom row is for the piezo, so it's easy to find things on my floorboard.
The Lifeson is a gorgeous guitar with top drawer materials!
I'd really like to hear from other people who use piezo equipped electrics. Share your setups or any cool ideas you have for using them live or in the studio.