Once you get past the warm summers, living in El Mirage is actually quite enjoyable. It's not too far from Phoenix if you want to hit up a big city from time to time but still has its own unique personality.
A good thing about El Mirage is that the houses are affordable. You don't have to fork over a lot of money for a nice home. The jobs are also decent as well. There is seems to be a good selection of full-time or part-time jobs available. What you will have to keep in mind is the summer heat, as you will have a good three months of consistent triple-digit heat during the summer.
For me, the best area of El Mirage was the local library. It gives you a chance to get away from the heat and still enjoy a good book. If you're retired and looking for a place to settle down, El Mirage may be a good choice for you.