Check out the Proteus X also. It's almost exactly the same thing. The only thing it's missing is the ability to sample, and sample editing functions. Both of which can easily be accomplished in any audio editor on your PC. You can use any wave or AIFF file as the basis of the sound. At $149 list price with a 2 Gig library it sounds like a good deal. I saw a demo at the AES show recently and it sounded good, and looked pretty easy to work with. The biggest bummer was that you have to have their cheap PCI audio card installed to use the software. Basically a dongle that uses a PCI slot!?!?
-Shehryar