I see that the most recent message in this thread is a couple of months old now, but for the heck of it I'll throw in my two cents.
This summer I got interested in freediving after having spent about a year doing scuba. Freediving fins are much longer than typical scuba fins. Also, within a given brand there are often choices of stiffness. Stiff fins are preferred by advanced freedivers who need a lot of power to get deep very quickly. Medium fins are easier for most of us who spend a fair amount of the day on or near the surface.
There are a number of different brands of freediving fins out there. The two that seem to come up most often are Cressi's Gara and fins by Esclapez.
A local freediver pointed me to a diving shop that caters to both scuba and freedivers, where the owner said that he has become a big fan of a new freediving fin marketed by Riffe, a company that primarily makes spearguns. The foot pocket I believe is made by Omer. They have a stiff version marketed under one name and a more pliable fin sold by the name Silent Hunter. I ended up buying a pair of these. On the minus side, these (like a lot of fin pockets made in Europe) seem to be made for a narrow foot, and I had to stretch mine slightly (using wooden splints while leaving the fins out in the sun) to get a perfect fit for my feet. But I have to say that they really cook. After being used to scuba-style fins such as Scubapro Jetfins and a different model of Cressis, I can really haul through the water with these freediving fins. Of course, it helps not to be slowed down by a tank and BC! ;-)