I'm borrowing a pair of these at the moment. Very good, very fast, covered in vulcanised rubber entirely and so they're at least as safe as anything else in use, moreso than many. The problem is the footpocket. For some people they're alright, but leaderfins needs an anatomy lesson. The big toe is not in the middle of the foot!

I need to find out if these ones are vulcanised. If they are, I'll take 'em.