Ok, so I've seen the Gillette Red Tip SS, Blue Tip SS and Black Tip SS. Essentially, from what I've seen, they all look like the same exact razor, but just with a different colored tip. I know that apparently they are supposed to have some rank of order as far as aggressiveness (and if someone could help me out with how they rank, please do). Is there any real difference at all between them the color of their tips or is it actually a bit more than just that?