Snappy, I'm glad to hear about the results you got. I use the Rock'n'Roll Gold lube, at the recommendation of one of their customer service folks, and I usually wipe it until it leaves no residue when I swipe the chain with a finger (my version of the "white glove" test). I get my bike with it's new chain back from the shop this week, so I'm looking forward to seeing how this works out.
Please let us know what results you get from Purple Extreme. I heard about that brand right after I picked up my bottle of Rock'n'Roll and I've been curious about it ever since.