Yamaha PSR300 or MO8 with SONAR

I'm purchasing a new keyboard and have been looking at two in particular.
The Yamaha PSR3000 and the MO8. (I've opted for the PSR3000 for now.)
They both have the features that I'm looking for (realistic sounds, editable patterns and grooves, etc.).
However, after doing some more research on the two, I'm wondering if the MO8 has a slight edge in the quality of sounds that it features, being that it is a newer model (I think).
I know that the MO8 is geared more to "contemporary" sounds, but does the MO have an equally diverse set of "tradtional" instruments on board? (Guitars, Brass, Reeds, Strings, etc.)
Of course, and most importantly, I need something that configures well with Sonar.
If anyone has any thoughts on these two keyboards I definitely welcome any and all comments!
As you probably figured out by now, I am not so much concerned with performance as much as I am with working with it in the studio.

Thanks,
-Harpo