My Nacra 5.5 Uni was faster upwind than the Nacra 5.5 SL and sailed a higher angle - by far. That was with one person on each boat. We had four 5.5 SLs sail against two carbon unis. The unis tacked faster, got up to speed faster, sailed higher, and the same or faster upwind speed. Downwind the SLs were slightly faster.

Reaching is were the unis don't do as well as the sloops.

I wish I had more time to discuss. I have a Taipan 4.9 that I sail uni, sloop, and both with spinnaker that I can give info on later. Got to get to bed now.