Old. Slow. Happy.
Velo Orange saddle rails?
Velo Orange mentions that the rails on their leather saddles are approx 10mm longer than Brooks' rails, but are they longer in the direction that will allow the saddle to be pushed back more?
For-aft adjustment of the VO saddle is affected more by the setback of the seatpost than the length of the rails. The rails are a bit longer because they are more squared off at the rear and they narrow closer to the front.
It appears that the VO rail design does allow the saddle to be moved further back than with a Brooks. But that's just from eyeing the photos on their website.
I just physically compared my VO saddle with a Brooks. The rear of the rails end in the same place on both saddles. All of the difference is in the front of the rails. So the short answer is that a VO saddle doesn't go any farther forward than a Brooks, but should go about a cm. further back.