Some who have experienced numb feet on a bent recommend shoes with the two-hole (SPD) pattern and sliding the cleat as far back towards the heel as possible. A few have even modified their shoes so the cleats mount in the mid-foot area. One might argue that since recumbent riders can't stand on the pedals, there's no need to place cleats right under the ball of the foot.

I get numb feet after 2-3 hours if I'm riding hard, but then five minutes of standing usually fixes that (When it's really cold the numb feet come much sooner). I've never used road cleats, so I can't say if they would feel different.