On the ABG side, if you are a Wizard or RapidRez user, you should always book your rentals via avis/budget and use the airlines codes for bonus miles as we have listed in the promotion thread. If you do not have a profile number, then we have seen the partner account number option doesn't come up consistently and using one of the partner portal sites may be more useful to enter that FFN or HFN.
The only car rental situation that I know of today at ABG that requires use of a partner (or rather alternative branded site) is Payless partner miles accrual options.
I am quite sure that more people want the auto-detect Wizard situation (via card number in this case) than not. However, I have not opted in to the Avis points program as an attempt to reduce the number of points currencies I am managing.
Rasheed