I had a psr 500 for awhile, id say no, its not worth $500 , maybe $350 because its just , well, old. It has sequencing abilities though which is nice for an inexpensive board although Yamaha makes a board for under $300 that does sequencing too. All in all I would pay $300 for it , otherwise spend that on a s30 or xp10 roland.
I have a Yamaha PSR6300 that I gave $500 for and know now that I got ripped off. Like shem said, it was an 'old' unit, and knowing what I know now I wouldn't pay a dime more than $300 for even the newer psr 550. IMVHO.
