Ron Guth: Mintmark positions can and do vary widely on most Lincoln Cents and should not be used as a means of authenticating a particular coin.
David Hall: The 1911-S is one of the better Lincolns in all grades. Among the early dates, in circulated grades only the 1909-S VDB, 1909-S and 1914-D are worth more than the 1911-S. The 1911-S is very scarce in mint state and rare in Gem Full Red condition. Interestingly, in Gem Full Red the 1911-S is a little more available than the S-mints that follow.
Most 1911-S Lincolns are decently struck. The color on Full Red examples is a little more subdued than on the later issues.