Biggest reason - TOO DARN WIIIIIIIIIDE!
It's a full inch wider than the 3k, and that means a new case, a new setup on my stand, new viewing angles ......too much change for something that is too similar to what I replaced.

The key feel was just like all the PSRs have been. The case was just too bulky for me to get excited.

If you want a Tyros and can't afford one - I guess this is the poor man's version, and it's priced right ( especially the s700! ), but if you already have a 3k ...... better play it a lot b4 you decide that you need the upgrades.
Some nice things were the extra buttons that have been missing for DSP and ensemble, and it IS pretty. Just too thick for THIS uncle !