First, I've been a keen fan of the Ozone Reo since 2013, with a 6,8,10 quiver ever since. I've stated my view here a few times since then, that they're a fabulous wave kite and 2014 was a standout model though I didn't find any real substantial improvements since then. I still have V4 as V5 reviews sounded pretty mixed to me. My 15yo son has been sponsored by our local Newcastle kite shop for a 3rd year with a kite of choice, 9m Duotone Dice. I have absolutely no previous experience with the Neo, but I have had access to the Dice. 2019 and 2020 didn't really take my attention, apart from noting the amazing wind range, but I've now had a few good back to back tests, albeit my used, V4 10m Reo vs spanking new 2021 9m Dice in difficult marginal side to pretty onshore wind and that really opened my eyes to Duotone. The Dice clearly got going earlier and made ground much easier, but it also surfed down the line really well.
I was excited to hear news of the new Aluula and was considering just one, due to the cost. And then Duotone springs this Penta on their new SLS Neo, at only modest additional cost, where I could perhaps justify a whole quiver.
I've laid a 2021 Neo SLS 9m over a V4 10m Reo, not a full metre difference in area I would say, Neo is much higher aspect. I weighed the Neo at 2563 and the Reo at 2792. I'm pretty sure the Neo has the bigger bottom end, though I haven't back to back tested, loops just as sweet on the wave, and light wind foiling clearly leaves the Reo for dead. I was apprehensive of the Neo for its reputation as more aggressive, but found it to be as smooth as, and landing jumps strapless are so gentle.
I think Ozone Reo development has stagnated for some years and allowed the competition to overtake.