Psst... they called you-know-who Darth Vader on the Mustafar Playset box too. 
Must you always kill my buzz, Jeff?

Seriously, the vertical lines on the thigh armor are not there (at least on my figures). The blue lines around the bottom of the knee plates are painted on, but none of the three have the blue thigh paint. So there you go.
Otherwise, the figures are, quality and accessory-wise, what would happen if the running change to the #6 Clone was as a 501st instead of a Shocktrooper. The only real difference is that none of the three 501st Clones included have the removable shoulder armor, as the solid blue piece has been glued on, and no alternate Imperial piece is included. No extra non-lightsaber hand for Vader, either.
The Clone Pilot is still the WTF? figure of the set. They could have thrown a fourth 501st Clone in and I don't think anyone would have complained.