My company restricts our car company rental to one company. We were using Avis, but then switched to Budget because we got a better deal, then switched back to Avis because I guess some people found Budget inconvenient compared to Avis.

Anyway, while we were with Budget, I thought there reward program was great, even when Avis was still giving us 500 miles/rental. After two rentals you get an upgrade, and after four rentals, you get a free day rental. I did find it difficult to get the upgrades, BUT in one case I was on a trip in Orange County California and got upgraded from a midsize to a convertible ... that made it all worth while!!!

The free rental certificates were a little screwy from what I remember, but they worked fine for me and I thought they were well worth it.