I've dealt with it a few times. First time was watching a neighbor with a roller, and he totally screwed up the surface - the more he worked, the worse it got. He eventually took it down to ceiling board, and retextured it. Second was an almost pristine late 60's ceiling with a LOT of the original mica/asbestos "starscape' flecks... I didn't want to lose it, so I used my regular spray gun and clear coated it 3-4 times - turned out surprisingly well, BUT... the room needed to be aired out a couple weeks, I should have been wearing a hood, a real PITA. I would think long and hard before doing that again. The last was using regular ceiling paint and an airless (it was an in-law bungalow, and whoever lived there you'd think used it as a cigar lounge... Ugh!) and that actually was fastest, easiest, and decent results.
Personally, unless I had a place I wanted that 60's-70's cocktail era vibe, I wouldn't touch that **** again. God, what a hassle.
Side Note - I found you can still source the mica flakes for that 60's-70's sparkle. How "groovy" do you want your "pad"???