I use the Ascentions STS. The clip on the end on one of them kept falling off...so much that I've lost it completely. The skin doesn't come off, but the strap flaps around.
My Scratch BCs don't have a way of securing the clip. That would be really helpful since it always seems to eventually slid off.
I'm also a little frustrated with the "custom cut" idea. I spent a lot of time doing just that. They fit perfectly when I started out. The problem comes when you take them on and off in the field. Invariably, they don't go back on the way you fit them. It's usually really windy, cold, or the wind has blown sand all over the bottoms of the skins. It seems like the "custom" idea is silly. I'm almost thinking Old's-cool and going with the straight strip that goes down the base.
Not to be misconstrued, I love these skins, I'm just wondering what real advancements have been made over the years to ask $130 for them. Perhaps REAL seal-skins are cheaper!