I'm new to guns as well, but from what I have read and experienced so far the longer barrel will help with accuracy. (The specific reason why is slipping my mind right now though.) Also, I would imagine that the added weight from the slightly longer barrel would assist in reducing recoil and less muzzle flip which can help follow up shots be in faster succession.
All in all I would say the longer barrel has no negative affects on your intended use. Shorter barrels are usually preferred for carry weapons and since that is not why you are buying a gun you should be fine with this purchase. (which by the way seems like a rather good deal IMO)