i have yet to try one of those Park or Pedro's chain cleaners, but i hear good things about them.
when i clean my chain, which is only once in a while (i try to keep it clean as much as i can), i take it off and let it sit in paint thinner/solvent over night. The next day, i take it out and blast it w/ compressed air. You'll be amazed how much crud comes out when you blast it! Let it dry properly before you put on some new lube otherwise the leftover solvent will dissolve the new lube.