Had a 6'1" x 23" @ 105 litre Kalama E3 (the orange board in the photos) and used it for winging in all conditions, gets out of water in light winds (sub 8 knots) with big wing and foil and absolutely loved it.
Grabbed a used Amos Sultan 7'2" x 19" @ 103 litres on a whim to see what all the fuss/hype was about, wow this board is fast through the water, first time out taxiing through the moored boats and I could see how much speed I had with hardly anything in the wing. As everyone comments, the length disappears as you are standing amidships rather than at the stern. Definitely very easy to get up in light winds, very stable, doesn't slow down on touchdowns blah blah,
One downside I noticed was the board getting turned downwind when I was in the water and trying to get going again in waves/wind. Simply spin the board by pushing the wings leading edge and sometimes hang the upwind leg over the edge of the board and drag it to keep the board tracking across the wind whilst getting forward motion.
I kept thinking about the Kalama E3 and thought that my dream wing board would be a slightly shorter/less volume version. I came across a 5'9" x 22 1/2 " @ 95 Kalama (blue board in the photos) and now with a few sessions on this board I think Ive found the sweet spot. Took a session to get used to the fore/aft instability compared to the 7'2" Sultan, but Ive found I can get this shorter board going in light winds now that I have finally got my wing/board pump cadence in synch. The shorter board actually bounces quite high out of the water in 2 or 3 pumps and the Kalama tail/rail design releases the board very quickly and cleanly. I haven't had a chance to try the 5'9" in the surf yet, but the shorter length should let me slot into the troughs.
I had a session yesterday where the wind died when I was 600m from shore and this 95 litre board is easy to stand on and taxi or do a spinnaker run or kneel or lie down to paddle.
So for me this board is really best of both worlds, small enough to be a heap of fun, but big enough to be comfortable and energy efficient
For reference: Im 180cm and 82kg