We just returned, having rented from
Alamo. I'll reiterate that it depends on what code you use. If you use ALAMO'S code, you'll get a free additional driver.
I had initially used a different code, but when I changed it to Alamao's, the 2nd driver was free. (I'll add that there was no difference in price between the two that I was using.)
Using a coupon in addition to that should have no effect. I was still able to use the coupon I had, and still get the free 2nd driver.