This is not a review just my limited opinion as its the first "bigger" kitesurf board i got after an ocean rodeo jester:
I've got a 5'8'' 2019 Wam (standard) and also around 78kg. I have had it since January 2020 and ridden it everything up to about 2.5m waves.
I ride it stapped only as I like to launch off wave faces while riding out. Straps also give me much more confidence going in hard to turns on a wave in critical spots.
That being said... it turns well, rides very stable and reasonably fast. Upwind performance is not great in my opinion but good enough. I think it prefers to be under a fair bit of kitepower until the waves get a little bigger. Once the waves get shoulder to head high with decent power behind them it drops in nicely, can hold a good line sitting in the pocket and carrys enough speed for a good bottom turn, top turn combo. For me I'm happy with the 5'8'' and would not go down to the 5'6'' due to the smaller volume. I have the jester which is way more fun in small stuff anyway.
It also came with a full traction pad on purchase which still looks strong wtih no peeling or lifting anywhere.
My only slight complaint is impact dings from launching off of wave faces (see photo).