Cressi Reaction Pro Fins

I bought a 42-43 (size 8-9). It fit like a 9, very loose for my 8 1/2. I ordered some neoprene socks and I hope that will make for a better fit. I almost feel a 9 with a neoprene sock would be the best fit.These fins are about 4.5 (11.43 cm) inches longer than a traditional snorkeling fin and wider but I didn't measure, about 2 inches. I use them to workout in an Olympic pool. The extension in my kick felt similar to my last 2 fins. The flexion felt slow, weak, a little off. I'm not giving up on these fins. I didn't like the last pair when I replaced the previous one, at first. Adapt and overcome. It is a very rigid fin.