I was mixing 10 liters of ID-11 every month and used it 1:1 to economize, and basically got tired of constantly mixing chemicals.
I now use Diafine because it gets reused and does not need replenishment, in fact it gets better mid-tones as it gets seasoned. Also has an almost unlimited shelf life. Basically I have to add volume for losses due to wetting film and spillage.
The bad is that it is a two part contrast compensating developer that adds an extra step, but the times are short. Also I found the suggested film speeds to be too aggressive that led to thin negatives, but now I shoot Arcos at 100 and Tri-X at 650 and get detailed negatives that I can straight print in a wet darkroom.
I generally process 40-50 rolls a month and the cost of processing is a few pennies worth of fixer and the cost of film which I buy in mass quauntities for a discount. Many here on this forum dislike Diafine, but I get great results and spent the time to get it to work for me.
Cal