I installed the HID kit, just make sure is for the right light bulb in the corolla case is H11, check first.
The other item to check is the power, you can get 35 watt or 55 watt. I took the 35 watt as I don't want my battery to go flat very fast if I left the headlight on by mistake.
Finally is the ballast there is a standard which is 1.5 cm thick and the slim one which is 0.8 cm. and smaller.
I got the slim version and no problems after 3 years. I only replaced 1 xenon bulb 6 months ago.
Check your state legislation for high discharge headlights as your only meant to have them if there is a washer installed and the head light is a lens focused type. where I am there is not legislation for that.
keep your head lights clean so the light doesn't affect other drivers and have fun!!!.
I picked 6000K color which is slighly blue and added some LED bulbs (T10), mine has 9 led 2 on each side and one on top besides it matches the headlights color.
same for the rear park lights, and changed the plate lights for the 1W LED (T10). consumption wise I reduced the car consumption from 85 watt to 39 watt. so I won't be getting another flat battery Bahahahahah.