If you're inexpensive lamps have plastic sockets which are rated for no more than 60 watts you're risking serious fire hazard. There is a difference in the quality of heat lamps. I know some of the expensive ones at pet shops aren't any better than those at your LHIC. Some are much better for the same price.
Things to look for in a good dome lamp. Heavy ceramic socket. Check the tab in the bottom of the socket, the heavier that tab the better quality of socket. Flimsy tabs will cause you to burn out bulbs faster. Heavy cord and plug. Lightweight cords aren't designed to carry that sort of wattage and can overheat and cause fires. Cheaper isn't always better there's a reason why they're cheaper. They still have your money and you have a burned out wreck of a house.
I have a display in my store with the cheaper lamps, human heating pads next to my lamps and tank heaters. The cheap lamps were used with over sized lamps and the human heatpads the wires crossed. These cheaper products all began to melt and have charred areas. Even some of the reptile heat pads have nothing more than the cheap heat cables inside two layers of plastic. If these cables cross they will melt each other and can cause a fire. I find the Heatwave heaters that look like Flexwatt heat tape to be the best and safest.
Give some thought to safety when purchasing and using heating products. Don't let the manufacturers do it for you, know what you're buying and what makes it safe. Buyer beware.
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Hope this helps.
BigT