The Kurzweil is a great keyboard, but that K2500 will put you in the hole by about $3500. That is too expensive.
People may disagree, but I strongly believe that you would get your money's worth if you bough a Roland XP60 ($1300), the Country Expansion Board ($200) and then maybe buy a decent sampler (i.e. Roland S770 - $800).
You'd have all of the osunds you need with the Keyboard and expansion board. And with a sampler, you could have an actual musician come in, sample his playing. . and then play "him" using your keyboard (I'm trying to describe this in the most basic sense).
All together, you'd still be under the $2500 mark. You may even try to get this stuff used and maybe pay less that $2000 for all the items described.
The Kurzweil is a great board that will open up a lot of options for you, but even the basic Kurzweil setup is about $3500. (maybe $2700 used?).
If money is not an issue, then maybe. . . maybe go for the Kurzweil.
The Infamous EPU.