In my experience, Avis is better than Budget, though they're in the same company. That doesn't mean Avis is great. Just better. As long as your profile matches the promo you want to exploit in the rental. My main issue with them is my Avis First preferences going into my rental or governing the outcome of which partner miles post. Even if I've manually entered a promo code and my number and my name is the same - expecting 3,000 miles - they show up in another airline account - 50 miles. Or 150 for three days. And there is "just nothing we can do about it". With Budget, they often never show up, and "there is just nothing we can do about it". Except in one case they - a large slug of them - showed up almost two years later, after several FlyerTalkers et al apparently got to them through the local BBB of their headquarters.

I guess I'd say, the above commenters to the contrary, I haven't had very good luck with most partner promos, whatever the partners.