Fishie,
We are BIG fans of retractable, aft Biminis! On my 25 Sailfish, I could retract it, lay it on top of the hardtop and strap it all down tight in under 2 minutes.
The one you see in the above photo was never meant to retract as this boat was a cruiser only. I did have it modified to retract, but the guy did the job incorrectly and I'll be starting from scratch with a new canvas company. Hopefully, we'll be able to salvage most of the frame and canvas.
I may be using new slide tracks and other hardware that comes from a company in England. This should make it very easy to retract which is what you want while fishing. Trust me, even my hard core fishing buddies, love being in the shade while running back and forth to the Bahamas!
Perhaps, I'll take photos along the way and post up a report when the new version is complete. We'll never have another boat without an aft Bimini!