I have two sets of them that I use on my bikes, and have a few friends that use them, too. I switched to them from my exustar pedals, and I'll never look back on that decision. I've recommended them to everybody who has asked me about pedals for track. They can be run with double straps, but a single is really all you need.
My buddy hit a dog while practicing sprints on a quiet back road with them. He snapped his alpina track fork in half, but his feet didn't unclip.