I think some of the other posters have brought up a very good point on where you live will have an impact on good lens choices. I live in the North East where we have alot of green's and it's often cloudy/grey and find that something in the 15-25 % range works better than the darker tints. I like polarizing when driving because often times it allows me to see if brake lights are coming on in the car(s) ahead of the car ahead of me depending on the car of course. This really helps in stop and go traffic. I've found that some of the tints that shift color alot tend to be a little more fatiguing for me over time where some of the mild contrast lenses work very well. Right now I'm running OO Red Iridium polarized in one pair of fj's and vr28 in another pair. Both are rx lenses and I much prefer the OO Red unless it's really grey. The mild color shift of that lens isn't enough to mess with picking things up and it's a nice middle ground as far a light transmission. I'm interested to see the prizm lenses when they come out with an rx option.