Spending more money on another one may net you fancier options (recessed interior mood lighting, higher temperature fire protection, nicer lining material, exc.), but it wont likely do anymore to stop a thief.
AA batteries are pretty tough, but Stack-on combo safe's take four. Other brands take 9 volts. So get one of those to. Harbor Freight sells hammers for $3.99. Bring an extra 3" piece of wire pre-striped on the ends (pull it out of anything you like for free, 18 gauge is plenty thick).
Congratulations! Your now an official "gun safe cracker"!