Thanks for the insights folks. I just checked my National free rental day balance and noticed 2 days expire end of this December, I was not aware of that.
I do notice that the Exec Elite aisle of cars are usually slightly better than the normal Exec aisle. In many places that can mean a Chrysler 300S or if you are into it, a F-150 or Dodge Ram pickup. I also see the occasional Dodge Challenger in the EE aisle or Camaro/Mustang.
I think I will stick with National for now and I just enrolled in the 1-2 Free promo so that will be nice as well. Usually, I don't like expiration dates but I have had excellent service from National so no reason to change at this point.
Originally, about 2-3 years ago I moved off of Avis because they were so far behind on their loyalty program and ability to integrate earning points. I think they have caught up now but I'll stick with National until there is some compelling service or loyalty program reason to change.