I've had a TFI on my '07 Electra Glide for 6 years. It was easy to install and adjust. I recently installed cams, and got it adjusted to them in one ride. My friend with an identical bike has a newer version, and has also had good results.
For some reason I keep researching the high dollar, thousand adjustments, dyno required tuners. I haven't been convinced into buying yet. My recent 2,000 mile mountain trip averaged 43 mpg.