Not used them no. Only ss cassette style hub I've used was a stock part on a Trek District.
I used to use geared hubs with spacers but tend to go for freewheel hubs nowadays on my bikes.
Considering a lot of trials riders use Kings then I'm sure they'd fit your criteria, same is true of Hope though.
I think with the considerable differences in price - DMR, Novatec etal around £50, Hope around £150, King upwards of £400 - it's clear enough which will be the best hub without riding them or even seeing them in the flesh.
I'd say the Hope is popular enough with trials riders that strength and engagements are not going to be something you need to worry about, there's almost 100g between the claimed weights though, guess you need to ask yourself if 100g is worth a couple hundred quid plus.