I was wondering if anyone knew how long on average it took a ship to travel from place to using the Slipstream. In the show things seem very subjective, I am trying to develop an FTL system for a science-fantasy setting and I intend to base that system on the slipstream, but I have no idea as to the slipstream's travel times.
This is specifically answered in the show's "Director's Bible".
One interesting thing about moving through the Slipstream is that travel time has almost nothing to do with the distance between stars. If you're lucky and the Stream unfolds just right, you could get from here to the next galaxy in minutes. But if you're not lucky, and things get hairy, the same trip could take weeks or even months. About the only rule is that the more frequently a certain path is traveled, the easier and more predictable the journey becomes.
It's also worth noting that regularly traveled routes (for example, between major Commonwealth worlds) have drastically fewer 'decision points' and therefore can be traversed to at much higher speeds than locations on the outer rims or adrift in inter-galactic space.