Oh my yes, I couldn't live without it and it runs 24/7 and I don't care what it costs, I am NOT going to be hot.
Last week it was over 100 degrees all day, everyday and the house would still get hot (my grandmother had to have lots of windows in the house and now I am paying for it). It is significantly better this week and I am going to get some tint for the den windows to see if thta would help reduce some of the afternoon heat.
We also have ceiling fans that run all summer as well and with it as hot as it has been we have even used some small room fans in the den/kitchen/dining room area since it is so open and no afternoon shade.
If you live in the South, you MUST have AC
Suzanne