Folders are best for boat speed under sail, especially if you race.  They are not the best in reverse though.  You also have to give most folders a good kick of throttle to get the to open and grip.

    Feathering props give more instant response in both forward and reverse, and give you loads of stopping power and reverse grunt, as the blades revolve to always face the right way.  Feathering props have more “mecahnical bits” than folders, and need greasing every year.

    The Autoprop is a Marmite one.  Some people love them, others hate them.  The biggest critisism I’ve heard about them is that in a sea or a chop, they are next to useless and they keep changing pitch and you can’t get any drive out of them.

    I personally went for a Featherstream from Darglow when I changed from a fixed prop 2 years ago.  Sailing speed was noticable better.  Motoring speed forwards was the same as with the fixed prop. Stopping power was much better, as was reverse drive.  Propwalk almost went too (I have found that if you put it in reverse and let it tickover, the boat still walks a bit before going backwards, whereas if you give it a blast of reverse, it just goes straight backwards without any walk).

    If you want a good all-round solution for a cruising boat, I suggest the Featherstream.