Hi,
I had opportunity to test all of them and IMHO my lists are:
SOUND (sit down and close your eyes)
- Pa1X: best natural sound (like a band)
- Tyros: good sounds but a little too perfect, sometimes false
- G-70: quite distant from the first two. The sounds are not convincing to me
- Ketron: it's the last, but if look for traditional sounds (accordion and the like),
only in this genre is the best.
GRAPH. INTERFACE (intuitivity and easyness)
- Tyros
- G70
- Pa1X
- Ketron
SPECS (features - options)
- Pa1X (mp3, cd, full sampling, TC, configurability) it's the oldest but still hitting the road
- Tyros 2 (hd rec)
- G70 & Tyros 1
- Ketron
LAYOUT (usability, front panel facility)
- Tyros
- Pa1X
- G70
- Ketron
My final preference (all considered) is:
- Pa1X
- Tyros
- G70
- Ketron
Just sharing my opinion.
Cheers.