Should there be discoloration on the lens straight out of the box?
I'm not sure about discoloration issues. I've never notice any discoloration issues with mine I've had them for over a year and they work awesome. I use mine manly for long exposure shots. If you're experiencing discoloration perhaps you should reach out to the manufacturer or contact Amazon. Hope this helps!
In my experience, I did not notice any discoloration out of the box. The lens is adjustable from light to dark but other than the stock tinting, I would say "no". Hope that helps.