1854 Large Cent - Rotation Error

I have searched all morning on the internet looking around for information about a large cent rotation error.  I did read one comment on this site that says large cents have common rotation errors.  I also read a "itrade" offer for the exact same coin rotation, year, and denomination.  This individual tried to counteroffer to others that he would take $500 for the coin since a 2006 error book said the coin was worth $2500. 

I received this coin today and I was pretty excited to notice the error.  Guesstimating from the gauges available for identifying rotation errors, I would say this particular coin is somewhere around 65 to 75 degree rotation.  Funny that the coin mentioned above from "itrade" had the exact same rotation as my coin and they were calling it a 90 degree rotation.

So, do you all suggest I get this coin graded or is it a common error for large cents?

Thanks for you responses.

Because the Minting of Coins was Not like today
Yes Rotations Were Very Common.

Making them only Valuable to those who
want Them.

I doubt there is any set Value.