I personally can't stand the Roland OS, but its true that S-760 has a great rep as a 16-Bit sampler for its sound, kinda like the ASR, or even the MPC3K
Og's get alot hotter. Both technically have only 10 seconds sample time in 4 banks. There are some subtle cosmetic differences between the 2. Don't often see og's for sale, you'll be very lucky to get under 1k for either unit.