If you have a set of these - are any of your green locks significantly darker than others? Several of mine are very dark, so much so that it is hard to differentiate them from the red on a black background. Others are a lighter green. Just wondering if anyone else had this problem.

Your not the only one. I have had four different sets of these and can confirm for you that some were darker than others. I did have one set that matched and was of the lighter color but still very hard to see.

Paint the center number red/green respectively, problem solved.