If you find the DNC voices useful it may interest you to know that the 600 has a limited number of DNC (20) which are more or less equivalent in articulation to the Yamaha SA voices. However, the 900 has DNC voices (75 total) - some of which articulate like Yamaha SA2 voices. The benefit is that you're getting SA2-type voices in a Korg for thousands less than those in a T3 or T4.
Good point. That's the kind of information I'm interested in.