YMMV but as an National EE and a mere "Member" with Enterprise (although that's about to change 'cause I get Hertz 5* via Marriott (or AmEx, or ...?, I forget) and I status-matched to Silver) it seems to me that if I get National credit and/or get National EE status recognition on my Enterprise rentals (do I?) that it's better to stick with National, esp. since I rebooked with my corp number and discovered I could get a better car at the same price.

So at least for now, my strategy is National for on-airport rentals and Enterprise for off-airport rentals.