It doesn't look like the smaller Slipstreams will be available any time soon. I received an email from OMS saying that they're redesigning the foot pocket and changing the length of the new Slipstreams. The other choice for a lighter, stiff fin seems to be Dive Rite. I tried out a pair of Mediums last week,and while they're a little longer than the Slipstreams, I can frog kick and back up with them, and it's easier from me to keep my feet up while wearing them. They have nice spring straps included too.