Got UST rims and a ghetto conversion on another set of rims. All with standard non-tubeless Maxxiss tyres. Never had one blow off yet. Got Arch rims coming too and will see how they go. Not as wide as Flow but are wider than some.
I reckon a lot of it has to do with tyre compatibility with rim profile. Not UST or tubeless ready, just things like chunky tyres on narrow rims or vice versa. Seems Maxxis have more success at going up and staying up, even with regular tyres.
That and I’m sure weight has a fair bit to do with it. Those I’ve know to blow them off the rims are heavier than me. Not fat blokes, just a stone or two heavier as I’m about 11st. Well, plus they ride harder than me so slamming wheels into the ground hard 😉