I have indeed tried the XW-P1 - at my local music store a couple times. I'm very tempted to get it, as it has several features that I like that are missing from my year-old WK-7500, such as:

- Assignable controllers
- Realtime mix using sliders (hex mode)
- 8 levels on organ drawbars
- Real MIDI ports
- plus excellent synth sound creation possibilities and greater performance mode capability

Some things I still wish it had include Filter LFO for PCM and Hex mode sounds, simultaneous chorus and DSP (to get a truer organ emulation, among other things), more realistic rotary speaker and phaser effects, and better electric piano tones.

As a performance keyboard, I like the XW-P1 over the WK-7500, with the exception of fewer keys. I don't use the auto-accompaniment in a band setting, so none of the WK's arranger features are very useful in a live setting. But the XW-P1 with its real-time mixing and knob assignments - another story.

Now if ONLY Casio would allow the filter LFO on hex mode tones!