Hi Dennis,
I actually got one of the heaviest F16's around, as it is a homebuild. Mine is 121 kg ready to sail in 2-up mode and indeed 125 kg is about as far as I'm willing to go with respect to singlehanded handling of any catamaran. I can put this boat on its trailer and in its birth singlehandedly. Putting it on it dolly, flipping it over and right it again or dragging it to a point above the flood line is very doable in my opinion, but again I don't want to go passed 125 kg overall. Each added kg starts to measure in more heavily then the single kg added before. I too would love to own a modern F16 that are between 107-110 kg in 2-up attire. You do notice that 11-14 kg reduction, let alone the 45 kg that is the difference between an aging N5.2 and a new F16 !
Every now and then I'm asked to help a fellow club member to help raise the mast, flip the boat over or lift the bows to place the dolly underneath. Ever single time I thank the dear lord that I had seen the light about 10 years ago and have gone lightweight. I have never looked back ever since.
Wouter