I also got the Wahoo case/sensor and am quite pleased with it so far, but it hasn't seen any use outside my basement. I looked at all the available apps and found that a combination of the Wahoo app then uploading the data to ridewithgps.com is about the best for me. It's a manual process that requires a stop at your computer, but it works well.

The one feature that's missing from this combo compared to a Garmin 800 is the ability to upload or define routes and follow them on the iPhone. Hopefully someone will be developing that soon.