I don't have first hand experience of a long pre-labour but one of my good friends had her 3rd baby on Friday after 3 days of what you've described, and then less than 1.5 hrs of active labour She only just made it to the hospital and came very close to delivering in the foyer. So my advice would be to get to the hospital as soon as things crank up a bit as you ladies that have long pre-labour seem to go super fast at the end.

Good luck