I've heard good things about the conversion kit too. I already have most of Rick's parts for the conversion installed on my PD. Unfortunately, there are several special purpose parts for the kit, including a special diode board, stator, and rotor.
And there's the reason I decided not to install the kit on my PD. If I'm halfway around the world and I have problems with my stock BMW charging system, I can carry a spare rotor or diode board or get one from almost any BMW dealer and get back on the road. However, if I have Rick's kit installed, I have to carry his special purpose parts or order them from him.
If I were using my BMW locally I would definitely install the kit. For my RTW bike I'll stick with the stock charging system, upgraded with the solid mounts, Thunderchild diode board, Motorrad voltage regulator, and rewound stator.