I LOVE the GA Model Comparison Tool. It seriously reduced the complexity of the enormous spreadsheet I had been using for the task ever since the release of Multi-Channel Funnels. The biggest headache of my modeling has always been Direct Visits / Brand Search, which correctly or incorrectly, I treat similarly. My question is, how much do you trust that your Direct visits are really Direct visits (typed in or bookmarks)? In your "Make Love To Your Direct Traffic" post, you refer to "corner cases" where odd browser configurations, etc. make for not-really-Direct Direct traffic.