Ron,
I did the same thing a few days back. On my way to a gig with my Tyros 4 I stopped by a store and played the S970 for about an hour. Before leaving the store I thought seriously about buying the S970 - it wasn't bad at all. Then I went to my gig and played my Tyros 4 and it all became very clear - yes I'll keep the Tyros 4. Put them side by side and there is a big difference.

Deane