I'm thinking about it but have 3 main concerns - cost, installation, result.
They cost many times more than a good halogen light, like maybe 10 times as much, but you don't see 10 times better.
You usually have to have just one beam, either high or low, so need separate circuits for each. You can get dual beam units but apparently they aren't very good at either. And where to mount the ballasts is an issue.
Then there's those who say an HID conversion is not a good way to go, and that a good reflector with a good halaogen bulb is just as good. That for HID to be as good as they can be, the reflector needs to be designed for an HID application and not a conversion into a non HID reflector. Here's a guy who seems to know his stuff:
www.danielsternlighting.com
The R3 definitely needs better lighting at any rate. FWIW. VinnyBoy