Another thing to make sure is that you are supplying your amp with the proper voltage. You can buy the most expensive, heavy duty amp available, but if you electical sucks and the amp is seeing less voltage than required, then itll heat up fast and go into protect.
If it is stated as 1 ohm stable and you burnt the crap out of it, it could have been low voltage or a clipped signal which will both lead to heat and protect.
So if you buy a good amp and are afraid to burn it like the ones youve had before, just monitor the voltage and make sure it stays high. Even a good amp like AQ is no match against a crap electrical, clipped signal, or a bad ground.
Im not too sure on the recomended voltages for the amp, but im sure anything under 12 volts is no good for an amp or your alternator. Members like Loud that deal with this everyday can inform you a lot better than any of us.
The lowest ive ran my AQ is 13.7 volts and only during the peaks and ive had nothing but smooth sailing.