I was reading through the thread because I found out I could get a 350a alternator for the Expy and the info may come in handy someday.
What I can add is that I have been looking to add the second fridge next year for extended trips and am going through the same process that I did with the little A/C. I have found that most 1 ft cube fridges pull the same 1.3-1.5a as the larger 2 and 3 foot units. oddly you can find 10 ft units that use little more even though they are 10x the space.
The least draw I have found has been the Edgestar 3.1 two door. It pulls .64a which is only .04a more than a Grape 5 ft 12v fridge. Adding insulation can drop the daily draw down 40%.