Most people end up using a snorkel keeper. It's cheap, like $1, and simple. The bulbous things do not really help keep stuff out of your reg (if you are getting sand in your reg, you are either a cave diver or you have horrible bouyancy skills) (and remember, you can puke in your reg. Getting some sand in it won't hurt it as long as you actually rinse your regs), and doesn't really help keep it from freeflowing (if your reg is that touchy, remember it's your octo, get it detuned a tad.)
And most divers who are in tone with the DIR mindset use a necklace, which is actually probably smarter but works best with a longhose setup.