Scott,
This is what was said on another site....

Here are some of my concerns - there are more
1. The ability to switch styles in the middle of a number and maintain tempo (i.e. no tempo lock)
2. The ability to select (ON/OFF) bass inversion during a song - you can do it with several button presses
3. Seeing the length of INTROs (countdown)
4. Being able to play one's own chord sequence for INTROs/ENDINGs
5. Having complete flexible control over FILLs and VARIATIONs - No control over fills - needs FILL buttons
6. Having STYLE part volumes and muting/unmuting available without switching screens.
7. Having AI fingering work for major chords by just playing one key (hasn't worked since Tyros 1 - despite its specification)
8. Screen page management is often a nightmare - would like a one-click-to-home-page or auto return.
9. Too many button hits to get the UPPER sounds ON/OFF and selected.
10. T3 vocal harmonizer is unusable - very poor quality - haven't actually bothered trying the T4's VH but I believe it is better.

One of Yamaha's answers to their OS shortfall is to use REGISTRATIONs - these are NUMBERS and cannot be easily selected unless you remember them all
Overall too many button presses to achieve useful performance features.
It seems that all they have focused on is SOUNDs which would be great if it was a sound module, but as for the "ARRANGER" component it just does not cut it for me
The Tyros, although very nice sounds, is far from a professional arranger.
If you are considering one, PLEASE borrow one and try it - set it up for a performance and you will see what I mean.

What does everyone think of these statements?

Thanks again,
Lee S.