In 40 years of working burglaries (among lots of other stuff), I know a few things. Real gun safes work for the vast majority of people simply because the most common burglars are amateurs - kids mostly. Professional burglars (not crack/meth heads) are after cash and valuables easily fenced, not long guns as a rule. As with everything, there are exceptions.
One fellow collected Lugers. Took off wooden grips, stored them in 5-gallon metal buckets of motor oil - son of a family friend broke in, stole a trunkload of stuff, but didn't find the Lugers. We saw some amateur attempts to open gun safes, none worked if the safe was either too heavy to move or bolted down securely. Mostly, they did mess up dials, handles, etc.
One successful theft was a smaller gunsafe carried off and accessed through the bottom of the safe with an angle grinder. Bolt yours down.
In fires, when the floor is weakened, safes fall through. Stuff inside not cooked, is ruined by water as well. Best place to put a safe is bolted to a concrete floor. Get insurance. Good insurance. Keep a list w/photos.
Outside of the rare professional burglar, it may not be someone who's seen you stuff that breaks in, but someone who's been told about your stuff by someone who's seen it and ran their mouth. (workers, friends, family - "I know this guy with some neat guns." Anyway ...good luck.