Or no sealant for that matter.

Which is the best option for keeping it fairly light and reliable?

UST & tubeless-ready seem to have thicker sidewalls and also a wider "foot" to the bead. I suppose these are both good things but also heavier.

ive got tubeless on back and non tubeless on front both with 'milk'

Good question. For the wife, I've set her up with normal tyres and sealant but on mine, I use UST tyres as I've damaged some sideways with normal setup. I put 60ml of sealant each end because I can't be bothered to stand there in the rainand fix a flat (it's always in the rain). However, there are tales of sealant upsetting certain tyres.

What tyres and what sort of riding are you thinking of?

Onzadog – that's the million dollar question. Not a clue what tyres i'll settle on. Haven't tried any Maxxis XC tyres, so might have a punt at them. Riding = Jeycore XLite.

Jeycore Xlite you'd probably be okay with normal tyres and sealant. I tried to push the envelope too far and used Maxxis eXception tyres in the Peaks. It didn't work out well. Having said that, I ride the peaks with a mate who has normal Kenda Blue Grooves and sealant and he loves those and not had any trouble. I rather like the Maxxis ADvantage right now.

i ran mine with normal tyres and sealant

You definately want sealant IMO, sure you can go without with the right tyre, until you puncture, which you will. Woeth saving 60 grams for? I reckon no. You might save a minute on a climb, or you might lose 5 with a puncture.

I'm still experimenting, ie fannying about with tubeless on nevegals so far, just standard ones and it seems to work well enough. Not actually lighter on my 717s, mind, a stans strip and the recommended amount of sealant is heavier than my standard rim tape and an XXlight inner tube. And those are pretty reliable tubes, not silly weight weenie kit. But that's not the whole point of course. On my traversees it'll be about 20-30 grams lighter I think.

I had a load of trouble getting an old one to seal due to previously unnoticed sidewall damage, which I think does prove what people say about thin sidewalls- what was irrelevant with tubes was a real pain with tubeless.

as you know goan im running none tubeless tires no issue. only puncture ive had on my tubeless was an inch gash from a rock in the sidewall of a rocket ron.

always sealant

ust tires for rocky courses – most stuff you will be doing on race courses will be fine on standard tires

Depends what sort of punctures you suffer, in my area i have a lot of flint and useing normal tyres with sealant is very unreliable with cuts because the tyre caseings aren't thick enough.
But tubeless tyre caseings are more meaty and the sealant seals much better, its a little heavier but i prefer not fixing punctures also with the innovations tubeless tyre plugs even puncture that won't seal are delt with in a few seconds.

I'm getting on very well with Bonty tubeless-ready tyres and sealant. Jones ACX 2.2s on the full-sus and a mix of Revolt Super X 2.2 and Jones XR Team Issue 2.0 on the hardtail, which is what I rode at 10 More in Moray.

Rims are XM819, XC717 with Stans rimstrip and Shimano XT UST. Very easy to set up and seat the tyres on any of these rims and a "glug" of Stans sealant does the job just nicely.

I've had a few punctures on the rear wheel with the full sus but usually down to reckless riding and slamming the back wheel into cross drains which can tear the bead as the tyres are very light and a bit fragile for very rocky riding. The tyres on the HT have been brilliant. Very light too (sub 500g). Only one puncture which was a loud pop as the inner and outer casings de-laminated, but it was an old, shagged tyre anyway.