Experience with LED bulbs?

I'm thinking about putting in LED bulbs in the Tail/Brake lights, Front & Rear Turn signals, and back up lights. There are several sellers on E-bay with very reasonable prices. Anyone with input (good or bad) Please reply.

I got to play with a couple of the ones that have the fold out wings with led's on them. There was about a fifty percent loss of brightness with them. The wings blocked the light from bouncing off the refelector. I read somewhere that ford might be introducing them on the crown vic in 08 or 09 with a redesigned reflector, but I don't remember where I saw that info.