From some quick tests in Bari:
There were 4 designs available for trial, a hockey and a rugby fin from leader, a hockey and a rugby fin from Nemo (or finswimworld.com or whatever).
Of the designs on offer the Leader fins were the fastest, but the footpockets are positively destructive unless your feet are shaped like sandwiches.
The Nemo hockey fins had fantastic footpockets, comfortable with good acceleration but the top end was half a second slower than the Leaders.
The Nemo rugby fins had no ribs, so slipped sideways in the water easily, which sucked. The designers of fibreglass fins in general don't seem to have picked up on the concepts of laminar flow and directional thrust yet - there's a reason every pair of fins in the world has ribs...
I didn't get a chance to steal some Mat Mas fins (they weren't on sale here), but while the blades on them are a little larger than the other varieties, the construction doesn't appear as professional.
All the companies only had medium stiffness blades available which was a pain as I'm suited to stiffer fins. I'd like to see if the hard varieties alter the speed/acceleration characteristics much.
In general, the fibreglass fins on offer thus far have had their design driven by the needs of uw rugby, which seems to require good acceleration and mobility, but not need much top end speed (please correct me if I'm wrong, I never got the chance to actually play). I think another year or so of development will see some very nice fins floating around...
I'll definitely be wearing fibre in Durban.
Oh, and these guys weren't there, but the fins look at least as professional as anything else out there.
http://sportsbutikken.dk/catalog/pro...roducts_id=483