Is it worth grading a mint bought gold coin?

[Jose Cuervo junior]

Is it worth grading a coin from the mint that is already in a protective case?

[Conder101]

Usually only if are absolutely sure it will grade out as a 70, and you are planning on selling it.  Most modern coins from the mint that grade as 69 or less often do not have a increase in value great enough to offset the cost of submission and slabbing so they end up being a break even proposition at best.  And if you don't plan on selling it, what does it matter if it is a 68, 69, or 70?  If you have a beautiful coin in your collection, are your really going to enjoy it any more because it is a 69 instead of a 68? 

Stored in their protective capsules and stored in the proper environment (Low humidity and steady temperatures) the capsule is probably about as protective an environment as a slab would be.  Only advantage to a slab would be if you are clumsy and have a tendency to drop your coins on uncarpeted concrete floors.   Slabs are a little less breakable than mint capsules.