For those of you who spend hours and hours in the sun, ummm, on your tractors of course, tell me about your sunglasses choices. Son will be in Wyoming for 6 weeks around 7,000 ft for a geology project. We have just about everything together but decent sunglasses. I realize I could just drop $150 and grab a pair or Raybans, but I'd like to get something protective but less costly if there is such a critter.