I think that with the method I wrote about earlier, you just need to leave it in the dye for 10 minutes or so and then rinse it off. I'll check on that, and if I find out differently, I'll post here.
edit: yeah, checked it out. He brings the rit solution to a boil, let's it cool down for 5-10 minutes, then floats the disc for 5-10 minutes, rinses, and removes the vinyl.
Also, as far as plastics go, champ/z plastic is supposed to be the best, star plastic is good, but will fade more quickly and can apparently bleed easily in the rinsing/vinyl removal process, and pro/x plastic is supposed to be pretty good too. I think I heard somewhere that the acetone method isn't the best for pro plastic--it eats into the plastic if left on too long or something. DX, I believe though, is pretty much crap for dyeing. As for glow plastic, I haven't heard much, but one dude did this one glow TL up:
As far as I know, he did it in the same method I mentioned...don't know about the longevity of the dye or anything, but he obviously did something right! These guys make it look so easy, I'm a little apprehensive as to what my first attempts are going look like.