Other Car Rental Programs (ie. Alamo, Enterprise) - Are the small companies always cheaper?

Over the past year or so I have had to take cars on rent and have always found the small companies such as Advantage payless, budget to be the cheapest. If was not always this way. I have used the discount codes and the rate on the big companies such as Hertz or avis never seem to be competitive. Anyone else feel like this?

Nowadays I don't even check the airline mileage offers that I get.