Håkan,

if the sailarea is limited by class rules, an uni rig might be the better choise, but otherwise I think the rigs are more equal? Mathematically and theoretically the uni rig is better to windward when sailarea is unlimited, but I am not certain if it works out like that in the real world? Low aspect rigs are good in high wind condtions when high aspect rigs become overpowered (Hobies did well during SM, but the Tornados struggled). The M20 is the only 20 foot uni rig with some success so far and they seem to be doing well at distance races as well, or? At the same time, it's been quiet around the F-18HT.
Anyway, I think the Tornado rig shold do well on both a distance racer and up/downwind. These days the rig is optimized for up/downwind, but it's fairly good on a shy reach as well. For a proper reach an overlapping jib would be better, but the selftacker is so nice to sail with that you would not like to drop it. No selftacker would also make the boat slower downwind.
In the end the sloop rig should be more versatile while the uni rig should be the best upwind. Selling point is: you can pick up a very advanced, well known and fast rig at a good price with affordable used sails. Will a modern platform designed for the Tornado rig be faster than a Tornado both around the course and distance racing? After all, the Tornado is still the benchmark. Who knows? But finding out will no doubt be great fun. I know what I believe <img src="http://www.catsailor.com/forums/images/graemlins/grin.gif" alt="" />