Don't know but a few pro players who frequent the boards including our own @htimSxelA but if you're willing to take comments from us mere mortals I'll throw my 2 yen in. The quick answer for most people would probably be the Sweets pro model but if you're comparing that to the Ozora ReShape 2 then the answer might not be so easy. All things equal ( material, weight, balance etc.) they're both really nice. Ozora ReShape paint is a bit stickier than their Premium paint, so I've been told by the factory, so it would compare favorably I think to the "stock" Sweets Sticky Clear. However if you're talking Cushion Clear all bets are off; in most cases I prefer it over the Reshape paint. On the ken itself a lot of that is going to be shape preference and whether you get the weight and balance you like. If you have a great Reshape 2 next to a marginal weighted/balanced Sweets then many might prefer the Reshape; same in reverse. Feature-wise it also might matter to you if you like the base cup hole. With a well balanced setup you don't really need it since it is more of an "equalizer" feature that is trying to bring more consistency to all the kendama made with it. i.e. it's easier to drill a hole in the base cup to relieve some weight for better lunar balance than weigh all the sarado/kens and try to match them up to achieve the same effect. If you're looking for a recommendation on what to get next then I'd probably suggest going with something you don't have if you want to be adventurous. If you generally like what you've got now and just want something that is close but still different then go same/similar. All the different models out there are kind of like tools in a toolbox for me and I like variety. Some do things better than others and with a lot of options I don't have to try and force a hammer to be a screwdriver. Also the more variations tried the more you'll find what works or doesn't; everyone is different.
I'd say it just depends on what you're looking for, kendama is all personal preference, even pros like different shapes / whatever. There is no universal consensus. Do you already have a Sweets of Ozo ken? If yes, buy the other one, get some variety in the collection