Even the factory HID can be fun when an igniter that kills 3 sets of hid bulbs ($100 a set) and then to repair you have to bake the light or cut wires in a very tight location... Hope my w211 retrofit is less of a headache as i can't go back.
That said I do like the output and it can be fun to work on the car until you get frustrated and start throwing things and breaking expensive things :)

That's the major problem I agree completely, it's an excruciatingly small place and to take out the headlight you have to take off the front bumper which is way too extensive for a quick repair. As far as the DiamondVisions go, I miss the output of the HIDs but they do seem to have "broken in" a little bit and are brighter than stock, now seem to have settled into a fairly white color too.

Has anyone tried the new LED lights which seem to be more powerful than Halogen bulbs?

I have heard good things and bad things about them and would be interested to try one out but in research you really want to spend $100+ on a good kit.

I know they have some 5000k hits available I'm not sure if you will run into the same CANBUS issues or not, but I believe a few people on the forum have gone to them. I'm not sure who specifically. My other concern with LED would be the light pattern from the bulb not being optimal for these types of projects with the potential to scatter light, but I'd be really interested on a full review.