Red sensor is 60% VLT and a bit of amber-yellow~ish tint.
Blue sensor is 70% VLT and yellow tint.
On the red sensor people can't see your eyes much and has a red/blue/yellow mirror effect; on the blue your eyes are more visible and has not much of a mirror effect.
I'd say Red for cloudy to overcast... Blue for overcast to night. I have a red and really like it, would like to get the blue as well.
I wish i could have chosen lenses (would have gotten blue and red sensors), but my gripe is that i got the Scotty lago pro model and the bright light lens is really dark. I've never used that one, and doubt i'll ever use it in the area i live. I'd like to sell it, but it probably goes so cheap i might aswell just keep it for that bluebird park day if it ever comes.
Hope that helps.
Edit: Oh and BTW i'd trade my unused Gold sol for your Blue sensor.
Last edited by F1EA; 02-12-2014 at 05:48 PM.