The A500 Plus was actually a really nice upgrade from an original A500. It came after the A3000 and shared the same upgraded ECS chipset, 1MB chip ram as standard, with support for 2MB, and Kickstart and Workbench 2.04.

The A600 is near to identical to the A500 Plus in hardware capability. Only difference is the A600s 2.05 rom. Having additional support for the IDE HD port and the PCMCIA side slot.

So game compatibility is about the same for the A500 Plus and A600, with some older games that don't expect the 1MB chip ram, or sometimes the changes in the newer ECS chipset fail.

Strangely, at the time I had an A600 and a friend the A500 Plus and there were some games that booted and ran fine in the Plus but refused to run in the A600. No idea why. The ReLoKick 1.3 disk solved the problem.