the tiny extra amount of food used compared to barrows, is little enough to be outdone by the 90k repair cost of just the barrows chests. im sorry to say, but with 99 def it doesn't matter. also conisder that not everyone needs to hit more often, or the fact that a dfs can be used pretty much everywhere whilst a rune defender cannot i.e. metal dragons.
"not everyone needs to hit more often"? When, perchance, do you not want to hit more often? The one thing DFS can be used for is metal dragons. The 'tiny amount of extra food'? It costs me 3.2k an hour to repair my barrows chest, roughly 2 tuna potatoes. 3.2k an hour is virtually nothing when fighting, and that's for STEADY combat - something monster hunting is not.