Which Headlights should I get?

First step as others have said is to make sure the lenses are nice and clear vs fogged or yellowed.
in my 2010 Prius 2, I tried Beamtech H11 LED bulbs and while they looked brighter and whiter, the light did not stretch out as far as regular bulbs. It was just brighter directly in front of me and the light spread was terrible so i returned them.
I have since replaced my old bulbs in my low beams and high beams with Philips Crystal Vision Ultra and they are much brighter and a nice clean white light with great range.
Here are the H11s that i replaced my low beams with to give you an example of what i bought.

 

Guess what kind of work I did, yup, an electrician. There are two things that determine brightness, color and output. Output is how much light, for our use "Lumens" the more the better, then Color, typically this is about how your brain perceives the color. the eye receives the input, the brain analyzes the info, the most typical would be the higher the frequency the brighter it appears. So, low frequencies appear pinkish, "cool white", maybe 3000 to 4500, when the frequency increases it appears blue to white, typically 5000-6000 the brain says this bright. so look for high frequency and high lumen. Watts are about power and LED bulbs consume way less power then the others.
The bulbs this guy recommends on ebay are a good choice.

 

The bulbs are 6000 lumens and I have operated them as previously mentioned for over a year with no problems. Will they burn out,
yes they will eventually. They are, however, bulbs, and all bulbs do burn out eventually. The manufacturer shows a lifespan of 20000 hours. Will they last that long, that remains to be seen. I would gladly put new bulbs like these in that provide over 3 times the standard
amount of illumination every several years if necessary. The added visibility is worth the extra expense, at least it is to me.

 

Are there legal limitations to the brightness of headlights? Many years back I replaced the 55W bulbs in a car by 80W bulbs and only later noticed that they were being advertised as "for off-road use only" (as I think I have seen on some of the LED bulbs in the local store).

 

Yes, there is a legal limit. As I understand it, it's not legal to alter the bulb/fixture at all. DOT approved incandescent fixtures in the US can legally use only 55/60 watt (low/high) bulbs. I'm not aware of any LED or HID "retrofits" that are legal.

Having said that, I have LED retros (H4) in my Tundra, will be installing LED high beams in my wife's V wagon, and have an HID retro in my motorcycle.

 

I just did this yesterday on my daughter's Pontiac Vibe (Toyota Matrix). The headlights were extremely foggy. I started with rubbing compound to remove the oxidized plastic since it was extreme. Then moved up to the Mother's Aluminum Polish recommended by @ASRDogman using a sponge ball on a drill.

The results were nothing short of amazing.

I finished them off with a few coats of carnauba wax in an effort to offer some UV protection -- I don't know if that will help... but I figure it can't hurt.

 

You could have just used the Mother's. I used glass cleaner to clean them of any dirt or grim.
But as long as it works!

I was going to get one of those Mother's polishing balls, but $15-20?
I paid $4 for the buffer I used. I'm cheap with some things....

Though I imagine the ball did a better and easier job.
I'll look for a sale, and then probably get one.

Using the carnauba wax is probably a good idea. I'll have to do that next time.
I want to see how long this lasts.
I'm also trying to park with the headlamps away from the sun. I hate backing out of drive ways
and parking spots. So I usually back in, because it's easier and you can see better.

 

6000 lumens, or 6000K? 6000 lumens is about 4x brighter than Sylvania Silverstar Ultra. Could 6000 lumen bulbs really be legal?

 

Did you take before and after photos???

 

I didn't. I wish I had.

I tried just the Mother's polishing compound first, and it worked very well on the cloudyness, but the left headlight had some major oxidation that it just wouldn't touch... so I had to move up a step to rubbing compound. I'm not an expert, but what I do know is that working with finishes has to be done in steps: Wet sanding removes the most material, then rubbing compound is the next step, and polishing is the final step.

Time will tell how it holds up to UV.

 

" working with finishes has to be done in steps"

Indeed. Sylvania makes a kit that I have used with excellent results. Has three grades of wet sanding (the perimeter of the lens is protected with blue painter's tape), then some fine rubbing compound and the final step is to apply a clear coat that has UV protection.
Requires some time and a bit of patient elbow grease, but very good outcome. Under $20.00.

 

I used a similar kit (a few years ago) made by 3M that had everything you need including a sealer and a wheel to put into your drill to do the sanding and polishing. I did 2-3 cars with it, and still have enough material left in that kit to do 2-3 more. Also around 20 bucks. I can't say how long they lasted but my own car was still good about 2 years later when I sold it.

 

I used that on my Vibe. The second lens didn't come out quite as smooth as the first, but they're both much clearer than before.