I use photoshop cs5 and prefer using the pen tool to crop pictures.
Also, there is no gradation in this pic. Just a drop shadow.
Since this pic was very high rez, I didn't have to use the pen tool, just the magic wand which worked just fine. The whole process took under 2 minutes.
If the gun was chrome/nickel plated I might have had to use the pen tool for the best result. It was not the case here.

But...Thanks for your advice anyways.

How was talking about how to erase/circumvent the watermark. Having variable shading or gradation in the watermarks would make my methods far more difficult.