I'm still in the goofy honeymoon stage where my 650b tubeless G-Ones wor great, haven't worn out, haven't punctured and haven't needed more sealant.
So I think they're fantastic.
On the fitting JohnR, Jan Heine at Rene Herse recommends fitting tubes first as standard practice with their tyres, which have very flexible carcasses and are notorious for being hard to set up. Except that he doesn't do any miles on them with tubes - just fits them, inflates the tyre till it locks to the rim, deflates, unhooks one side, removes tube, refits the side, add sealant, amd inflates. Seems to think it always works.
I'm hoping to give his Switchback Hill tyre a try when my G-Ones wear out, so I hope he's right. Not that there's anything wrong with the G-Ones, they're amazing. It's just that Heine says his thres ride like tubulars, and I used to love tubulars formthe way they rode, so I'd like to give them a go.