I could hold a lot more wind with a Nobile 135 board than with an Underground FLX 128 - shape matters.

To add some more confusion to the mix . . .

Got to ride the 2013 Cabrinha Xcaliber and Tronic here in flat water and choppy waves, powered enough to go upwind.

The Xcaliber was very nice, I mostly liked it BUT it's quite stiff - if I wasn't paying attention in the chop, I got bounced around some.
The Tronic was smoother through the chop but had a constant stream of water from the leading part of the heelside curve straight onto my back leg. None in the face which was nice.

The Tronic has much narrower tips than the Xcaliber . . .

Then I jumped on my Flydoor and had a good ol' romp - no spray on the legs at all.

So is it the width that's better or the curve of the board? I'm seeing some 142x47 freeride boards around that interest me . . .

105kgs, 138x41.5 WH Joke, excellent all-round board, no spray, great pop, cuts through chop. Yes it has quite a lot of rocker but it's fairly stiff. Sacrifice some on the low end but then its time for the surfboard or the skim.
Have tried as many other boards as possible when at the beach but still loving the Joke!

Murph.