Take this for what it's worth but I had a chat to a guy who was shredding on one at Bronte in 4-5ft waves about a year ago and he was making it look easy, The waves/conditions were really good and he was carving them up and hitting the top. He was around 90-95kg and rated it even though he'd borrowed it from a mate. He said that he normally does not SUP and just rides short boards at the same spot.
Looked impressive and fast on those waves, and a pretty beastie looking board, definitely frothworthy.