Advantage of SA core is that certain additional instructions become available, benefiting optimised code. For example, several of our games, and also AMplayer and the like, have SA optimisations. They work on 710 systems of course, but operations that could be done in one instruction, then take many times more, reducing performance. There are also programs that only work on strongarm (eg. a few of our RO4/SA updates for the old Krisalis titles). I should stress I haven't checked the above, but these are the benefits I would expect to see.
Also, if you have software optimised for hardware FP, the 7500FE core will probably help, as I'd imagine it offers a near-enough 1:1 mapping of FP operations to x86FP.