If you are in absolute need of speed than Micro Four Thirds is the right system for you You not only have the Voigtländer Nokton 25mm f/0.95 (Click here to see it on eBay) option but now also the Noktor 50mm f/0.95 is in Stock on eBay:
Sold by a Hong Kong eBay reseller (Click here).
Sold by a US eBay reseller (Click here).
I have both lenses and I use them mainly for video. For that purpose both lenses are very good. For stills the Nokton 25mm has a much better and “different” kind of image quality. It’s perfect to take shot pictures from my brothers baby!