If you are doing computer based recording as a songwriter, you have to also take into account, the difference in price and what you can get for the money. If the PSR 2000 is at least $600 cheaper when you factor in purchasing the hard drive and vocalizer for the PA80, you should consider what you can get for that $600. I purchased Gigastudio and some great piano samples and acoustic guitar samples. When I edit my songs, I use my PSR 2000 to trigger the lush acoustic guitars and real bass sounds that Gigastudio can offer.
All in all, you should think about what goodies you can get for the same price. For example, even though a Mercedes beats a Toyota Camry, you can buy a family sized boat with your Camry and still pay the same price.
You should do a search at this website with keywords so you can find out more about what other peoples' impressions are of these keyboards. Well, since almost no one has the PSR 2000, you can search for PSR 740, and realize that the PSR 2000 is a souped up version. It has about 20 more of Yamaha's newest voices, 20 more onboard styles, the capacity to hold about 20 more user styles, easy access to styles on your floppy disk, and improved access of voice and style registrations, and better sequencing features.