Power, when buying a gun safe check the spec's on construction (door thickness, wall and topthickness),resistant to attack (15min, 30min or 60min) TL=Tool, TR=Torch, TX=explosives. Compare rate of fire proofing ( Amount of degrees for 30min, 45min, 1hr), compare locking devices, compare combo locks( My preference is Sargent&Greenleaf three brass tumbler's key change.....that will give you 1 million possible combinations...100X100X100.....Also, if you have your home alarmed, incorparate it into your safe.
Pick three that you like and compare the above! I prefer Diebold and Mosler, but those are precious stone safe's and cost what most guys can't afford! $6000-$9000 and above!I have been doing this since 1976-2006, 30yrs. I don't actuallydo openings anymore, but get a percentage on different safe jobs that the young guys don't know how to do. My phone is always ringing!I still have all the drilling rigs, scopes, tools and manuels.

I own a Browning Medallion Wide Boy!

Edit:Always check the weight and what type of flooring you are going to place it on!