One comment on the protein grams to meat not - remember the bread has protein. That whole gluten thing lots of folks avoid.

For Arby's the bun itself is listed as having 7 g of protein. That means the roast beef is providing 16 g of protein. Double the beef and add the bun back in and you're at 39 grams. The difference in 38 vs 39 is likely a result from rounding.