My impression is that the V700s are more track oriented. The AO48 is very street capable by comparison, has less outright grip and should delive more track time. It may also be less camber sensitive which may be important for dual purpose cars without a full track alignment. For me, the drive to the event aspect of the AO48 is attractive, especially since I'll use them on the street alot. And the fact that the Elise cannot presently lug a track set of wheels and tires in it also matters. My M3 can easily take another set of rubber. The harder rubber of the Yoko should lead to reduced gravel being thrown up on the road. Rumour has it that an S version of the AO48 may come out, with a softer compound.
By next Spring more r-compound options may come out, and if you are not rules limited, also consider a 15/16 setup. The new Kumho V710 seems to be very good but no sizes exist for our cars presently.