Has anyone upgraded to LED HID bulb?

It's just an LED, not HID. It's a standard 40W LED bulb. I find that my LED vehicles are less bright and have a mushy cutoff compared to any HID vehicle. Meaning a 35W LED looks less bright than a 35W HID.

Being in London, these won't pass your annual inspection if they still do that.

 

I'm assuming your Prius has factory HID and you're wanting to change the HID bulbs to LED?

The reflectors on the car are built specifically for the type of bulb they were intended for (halogen or HID). If you use a bulb of a type other than intended, the most likely result is a bad beam pattern/excessive glare to other drivers. In most European countries and the US, using a bulb type other than what's factory specified is illegal for this reason. If you have the factory HIDs, you already have about the best headlight available for the 2nd gen Prius (from a light perspective, the reliability on the factory HIDs is reported to be poor).

That being said, some of the LED kits placed into projector housings provide acceptable light patterns with a good cutoff to prevent glare to other drivers. However, to put a projector housing on a 2nd gen, you need to go aftermarket, as the factory headlights (neither halogen or HID) are not projector housings.

 

AFAIK, UK Gen 2s are only factory fitted with halogen lights across all models – T3, T4 and T-Spirit.

 

Recently having read through many threads here and around and having the horrible HIDs in my 2009 I tried LED replacements. To say that I was underwhelmed would be an serious understatement. As mentioned by RMB above the light in directly front of the car nearly burns through the pavement while 100 ft away it's fading rapidly. Even with high beams any speed about about 45 is terrifying. Sure signs and such with reflective coatings show up just fine but I drive mostly rural two lane unlit roads. We have a lot of them but the deer don't wear reflective vests here in Michigan and since it's spring most of the lines on the road have been worn away over the winter as well. Add in rain to make the road reflective and visibility was completely unacceptable.

Compare these lights to my daughters 2006 with Halogens and it's not even a fair comparison, Halogen for the win going away.

The LED bulbs we chose (my body shop friend and myself) were from headlight experts. They looked nice and all and came in a very fancy box and claimed no wiring needed. Until you get them and they don't connect. When you email them they admit yes you need to splice into the wires. But they don't give you which side is + or ground. Another email and they tell you "Doesn't matter they work either way." OK Cool but please, say that. Then the light output, horrible and with no throw. I email them again. This time "Well they need to be pointing up/down" (there are LEDs on both sides of the board inside the assembly) Again, that's great but why do you not document it? They provided zero installation documentation. The things have the heatsinks on the back of the bulbs as most LEDs do which makes it nearly impossible to rotate them up down and there is nothing to lock them in place anyway.

And if you stand and look at the headlamps in low beam on both cars side by side the LEDs are splashing light all over any oncoming drivers face. Since i HATE THAT I cannot in good conscience do that to oncoming drives either.

And with all that they are technically illegal as are all retrofit LED and HID bulbs here in the U.S., or so I'm told.

Thus in the end we simply acquired a pair of aftermarket Halogen headlamp assemblies. (The car is 10 years old and the lenses a bit scratched anyway) I added a relay using the HID 'flipper' input to trip the low beams and we fitted the best Sylvania Halogens. Let there be light!

 

What about the properly designed Philips LEDS? They designed the LED beam to mimic halogen and are supposed to be suitable and legal drop in replacements.