Looking at AD-500 (A) ? or AD-600 (A) ?

[nesscm]

I have a APEX AD-703 (3 disk player) and have been having some problems lately. It's been hanging up a lot and I'm looking at replacing it with another (703), I was at SAMS yesterday and they were out, so If I have to get a different one, I was wondering which was the better of the two (500 or 600) ??

Thanks

[nesscm]

I screwed up, it's the 500w or the 600a or 660. I was also wondering are all these able to play what the 703 could. CD/CD-R/CD-RW/VCD/SVCD/MP3/etc. Are all of these upgradeable - hacks for macrovision/regions like the 703 was ??

Thanks