Good to here you're getting into the strapless. And good that your staying away from the 'production' kite surfboards.

I didnt like those boards for a few reasons:
General dims, I find a 'traditional' surfboard shape works best. For my 75kgs, I go for a 5'10 18"1/2 2"3/8
Outline, looks like too much tail vol for the 1st and 3rd board. Too much tail foam makes a board horrible in the pocket for vertical turns.
As said before, fin setup and glass. I will never again get a board (for kiting) with the twin tab fcs plugs... I bust them just turning, don't even have to touch the bottom. Futures all the way. And as above the JS boards don't hold up to surfing, let alone the punishments of kiting...
Condition, hard to tell through a computer screen but they look a bit knocked around (as a seller wtf wouldnt you strip the wax and present it properly?)
But ebay and gumtree are the place for boards. $250 should get something pretty nice!
Look at the completed listings section and offer peanuts for the boards that didnt sell.
Post up how you go with whichever board you get!