For accuracy? It's probably a little worse than quartz. The escapement will have a longer overall lifespan, and may need servicing every couple decades, as opposed to a new battery every couple years.
My Citizen Ecodrive needed the first capacitor change after 17 years of daily wear. Literally zero service to the watch before that.
Also I really really don't buy that this mechanical movement won't need service every couple years like pretty much any mechanical watch out there. Where do you take the decades part from?
https://www.seikowatches.com/us-en/customerservice/knowledge...
https://www.jomashop.com/seiko-kinetic-watch-ska791.html
Unfortunately, Seiko's "Kinetic" movements don't seem to have ever been a big hit, so I don't know if it's something people actually wanted.
Ultimately I think the "problem" is that regular solar watches work so damn well, and that most quartz buyers have no interest in "unique" movements. I mean, I do, but I'm the minority. And I still never bought one...
It's a bit of an oddity.
The lithium-ion power cell needs to be replaced every 5-10 years, and it's relatively expensive part.
It has more mechanical complexity than a quartz plus the same maintenance.
But it works really well. It's a hybrid.
I love it despite this, it's unusual looking and the quirkiness makes it fun to talk about.
I really appreciate your reply.