I guess everybody's body is different, mine blend in better with a tan and I've seen others say that.

Some of them are kinda silvery though and in some spots they don't blend, but the darker ones look much better.

Yeah they get lighter as they are older and start to fade.

Most of mine are silvery so that explains why they don't blend. Though some of my dark ones probably do blend when I tan, I just don't see them so I don't notice.