Of those on the page you listed I would consider:
Natural Balance
Nature's Recipe
Sensible Choice
Wysong

I would check the ingredients and see what sounded best to you.

Nutro Max is the lesser version of Nutro Natural Choice. Like Iams is the lesser version of Pukeanuba (or is it the other way around)?

Since you work at the store could you just go find out when they are putting an order in for the Royal Canin and make sure there is the size you want on the list? I mean you are a guaranteed buyer after all.

Good luck with whatever you decide.