48.34 BTC for about that price in difference ain't bad at all. Are they overclocked? Even if so, you should be able to calculate approximative power consumed. (or mesure the total electricity consumed by your whole rig including computer with an amperemeter.)
yes, most are oc'd and all with memory underclocked and running stock voltage. it will be easier to track going forward as i transition to dedicated miners. most of the first month was learning with much trial and error on shared pc's that already ran all the time anyway. my first dedicated fully populated rig pulls ~755W with 5 gpu's.