I had a stack on gun cabinet. I bought it when I first started out. It had a couple 22 rifles and a mossberg 500 in it. Two years ago I went on vacation. I realized that I had about $10,000 worth of guns in that $200 cabinet. I piled plywood and junk infront of it. I then parked my truck right up against it in the garage. About a month later I bought my safe. I paid $800 for it. Worth every penny. I now have about 18 handguns and 15 long guns.
If you are talking about a few cheap guns you want to keep away from the kids fine. If you have a valuable collection...get a real safe.
I have had a stack on for 3 years . It holds five long guns but of course it is a tight fit! It has two shelves and three locking points. Im not sure if you want combination, key or biometric lock . Mine is combination and you have to be right on every number or it won't open. I paid $350 for it and have been very happy.