Great article, Patrick, but I'm a little concerned about this line: "I will likely finalize the redesign and kill the old version in the coming weeks."

Please, please tell me that if you kill the old version you will have the numbers to show that that the old one is not, say, at least 5% better than the new one. At the moment you seem to be 'leaning' towards the new version even though sales from the old version are higher!

It doesn't matter how much time and money you spent on the new version, or how much better it looks, or how much easier it is to use. What matters at the end of the day is how much money it makes, so run the split test until you are (statistically) confident that you are not throwing money away when you kill one of the designs.