I don't think any single game ("the game" you mean but don't tell about) won't fit in 16GB. But if you plan to store a lot of video's on it, you better buy one with more storage.
On my PC, I've never regretted to have some spare disk space. But on an iPad, of course, it's more expensive, so you need to better balance your needs on one side and the money you want to spend on the other side. Since we don't know your needs nor the amount of money you have available for gadgets, it's difficult to advice.
Kees
ipad3 16G enough want start ipad3, prefer to play the game, will not tangle 16G too small? seek help.

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