I have a World Class scope I bought from another member awhile ago. I mounted it on the rifle and took it to the range a couple weeks ago. It shot ok; I had it on the highest setting the entire time. I got it back to the range the other day, and noticed that when I changed the power settings, the crosshairs tilted! I know Tasco claims to have a limited lifetime warranty on these scopes; does anyone have an email address I could write and get some more info?