I’ve lately got Amplid UNW8 2019 163. I don’t need it, my 7th board in the quiver now with a lot of overlap but I got a used one in a good condition for the best price ever so I didn’t hesitate for a second.
I haven’t ridden it yet but by hand flexing it is stiffer than any other board I have, stiffer than Pyre, Kazu, Optimistic. It’s really light for its size with a little torsional give, the biggest difference with other boards is the really stiff tips. I don’t have Rossi XV anymore but as I recall its flex it was similar apart from the softer reverse flex tail on the XV.
Many people claim that it is like Burton Custom X and I tend to believe it.