Assuming he would actually have made use of the R3 or 585 I doubt he is the type of rider that is going to have this problem. People who do are generally those who would hurt after any 20mile ride while those looking at 585s(even if not in peak physical condition) are more likely comfortable with 60+.

The pista is a decent track bike which means it's not ideal for as a road FG.
No rear brake mount(if you decide you want to switch to ss for more hilly climbs.)
No fender mounts(might as well make your rain bike the easiest to clean).
Track geometry.

There are plenty of road specific fgs that don't have these limitations now and may serve you purposes a bit better. If you think you want to start riding on the track soon as well the pista is probably your best bet though.