Sunglasses

I want low tint/clearish ones:

• to stop my eyes watering in the cold air, or when I'm doing more than 40mph downhill.
  
• to protect my eyes from particles, insects, or grit thrown up by traffic. There are cases of lost eyesight amongst cyclists, and I know someone who suffered pretty severe ocular trauma out on the road.
  
• to enhance contrast so that I've got more chance of making out road irregularities at speed in suspect/changeable light coditions.
  
• to stop me squinting, or my eyes drying out, giving me pensioner's eyes in my boyish face :p
  
  

I s'pose it could turn into one of those helmet debate type threads...

What tint is best rose, yellow or clear

I want some for the above reasons but I also kinda want to see where I am going