Perfect combo Brycol !
I have same set up as u on my King ... works really well imo (6' & 85kgs)
The full-on 18mm of concave sets these boards apart from the rest ... after u get into 'em it becomes evident ...
(i come from a surfing background and used to love deep deep channels)
It's like the deep concave provides a mini-hydro foil affect, and it funnels the water out the back more ... this is why they handle chop so well ... it provides lift & 'cushions' the ride, and i find i can ride for much longer periods than before
the rocker in 'em also makes them feel shorter than they are & combines well with the 18mm concave thru-out
the rounded ends means no face spray, and yes Funky they make the 140 seem small for a 140 ... I used to ride underground 138 and it dont feel bigger than that, under foot.
Single fin with grip ?
****k the way the concave works makes the rails hold so well, I've often thought I could ride even with out the 2 single middle-set fins sometimes - in extremely flat water ... and ****n great for super shallow sand banks when they crop up
BUt, I am biased, i ****n love e'm !
Hence I couldn't go for the CB wave and other biased boards. 
)
