just to inject a little sanity here; the combination of stans rims and UST tyres may not be an optimal one;
but then there is no guarantee that tyres and rims will work together as advertised. There never has been, and the required tolerances for tubeless are considerably higher than for other tyres. This was highlighted for me shortly after the announcement of the 'new tubeless tyre standard' (to widespread fanfares and jubilation): I helped someone fit a tubeless tyre to a tubeless rim, and basically it didn't ****in' work. The tyre was too loose on the rim, so wouldn't seat unless a booster bottle was used, and then wouldn't
stay seated for long enough to get the valve core in. Now I am a pretty persistent kind of a chap but I do tend to lose patience with obvious rubbish and after about fifteen goes I was all for packing it in. However my chum (somehow) found the motivation to carry on and by some miracle attempt number twenty-something was successful.
Now you might put this down to being 'just one of those things' but it happened that both the tyre and the rim were from the same manufacturer and furthermore that manufacturer has taken a leading role in the development of the new standard. So if
they can't make it work reliably with their own stuff then I'd say the chances of random combinations of various people's rubbish working consistently as advertised are not that good. Put it this way I'm not holding my breath any more than most tubeless tyres actually achieve their raison d'etre which is to
hold air. Some folk with long memories may remember it being a PITA with some tubs because they had flimsy latex tubes inside them which leaked air and you had to pump them up every time you rode the bike; its deja vu all over again in C21 with tubeless tyres....
IME tubeless tyres need to be a tight fit on the rim otherwise they are liable to be a problem when being fitted because they won't stay seated. However if they 'fit well' in this regard they are invariably more difficult to unseat too when this is required. Some folk have given up with tubeless rims because (regardless of the type of tyre fitted to them) they feel that they would be unable to get the tyre off at the roadside.
Above you will see a version of one of the choice phrases that is trotted out by tubeless advocates which is generally along the lines of "I've only had to put a tube a few times and it was no bother because it is
exactly what I'd have done with a tubed tyre anyway".
Ladies and gentlemen, this is what we scientists call "a lie".
When you get to the point you need to put a tube in a tubeless tyre you have of course already exhausted the gamut of possibilities involving sealant, daft things you are meant to stick in the hole etc. Then you need to break the seal of the tyre bead, which shouldn't be easy because of the tight fit but is also hindered by any dried sealant there might be under the bead. When you finally get the tyre bead off the rim you may wish you hadn't, because the liquid sealant in the tyre will start puking out everywhere even if it hasn't done so already. Sealant is intended to stick to surfaces and unfortunately most forms of clothing represent an ideal substrate. Many type of clothing are instantly ruined by contact with sealant. Now the tubeless valve stem has to come out of the rim. You will need pliers for this since the cretins that design this rubbish have not thought it through far enough. A (hopefully brief) 'slime wrestling' bout will then ensue as you try and get the tube into the tyre, only the tyre and the rim are not designed to accommodate a tube, leave alone one which is now covered in slimy crap. And the tyre will be tight going on again too, even if you don't pinch the tube against those often pointlessly, er, pointy lips inside the rim.
The whole performance has then to be repeated when you get home and do a 'proper repair', assuming that the tyre isn't going straight in the bin.
Needless to say this does not in any way resemble what happens when a puncture occurs with tubed tyres on appropriate rims, (provided you have not accidentally ended up with a bad pairing of tyre and rim that is tighter than it should be).
FWIW there are benefits to tubeless eg
1) if you think you might have a high speed blowout, the tyre staying on the rim better (because it is tighter) is a bit safer and
2) if for some reason you are determined to use tyres (eg all year round) which have all the structural integrity of a lightly reinforced condom, then it is possible you may spend less time (net) by the roadside fixing punctures.
But you would need to have a
lot of punctures to make the latter thing true, assuming that you are remotely competent at whacking a new tube in; this ought to take about a couple of minutes if you are in a hurry, and about twice as long if you check the tyre for sharps like you should do.
FWIW I may regret saying this but I have not had a puncture through the tread for about two years, during which time I have done enough miles across several bikes to have worn tyres out, suffered carcass failures and goodness knows what else. I use the lightest and fastest tyres you can buy when the situation merits it (which is not often), but guess I have done most miles on training tyres which are typically 50-100g heavier than really lightweight tyres. And I do check them for flints fairly regularly. So if you are happy to use tyres like that then tubeless is perhaps "a solution looking for a problem".
I am currently pondering a new wheelset and I might try tubeless again. My fallback plan is that if/when I get pissed off with it (again) I may just grind the extra lips off the inside of the rims. We shall see.
cheers