I would choose neither, but since it's about choosing the lesser ills of the two, I'd definitely take the first option—an igniting personality.
From personal experiences I have noticed that someone with a better personality at least makes me smile when I go home. On the other hand an intolerable personality, regardless of the extraordinary foreplay, leaves me disappointed at the end.
In particular there's one companion I saw three times. Excellent foreplay and intimacy, but had no conversation skills nor an interesting personality. No laughter, not even a smile. After each date I'd feel drained (not in the best way) and a little sad. I eventually decided to move on.