Not sure about headlight applications, but I love VLED's and their service...top notch. I am also a HUGE fan of their V3 Triton signal bulbs. Hands down the best LED plug and play product you can buy. I am probably going to be putting the Tritons in the front park/turn signals of the Highlander. I want to do the rear brake and turn lamps, but when I pulled the tail lamp assembly there is very little room for the V3 Triton LED bulb to fit between the assembly and metal body once its pushed back in place. So im thinking its not going to work there.
Keep us posted about what you do with the headlamps as I still cant believe this $45,000 Highlander still has halogen lamps!! I wonder how those stock projectors would handle and focus an HID bulb? The cutoff and beam seems pretty nice with the halogens, so I wonder if the HID bulb would be as nicely focused. If it were me I would probably go with HID's. Visit the retrofit source dot com for anything you need. They have complete kits that even come with a pre-made high quality harness. I might go that route, but I was kind of hoping someone else tried HID's on the stock halogen projectors first :-D