A Taco 007-F5 has a rating of .71 amps. Few draw more then .6 amps. 6 times 120 equals 72 watts. 7 times 72 equals 504 watts total, if all 7 are running at the same time. this should only happen on the coldest day/days of the year.
7 zones valves opened at the same time, plus 1 circulator(0010 since it has to move all the water) equals 188 watts. This would reduce your circulating wattage by almost 63%. And could probably pay itself back in 35 years or so. After factoring in the cost of valves, transformers, and wire.
Multiple circs, means if one ails, you still have the other zones that can keep you warm. With zone valves, if the circ dies, you got little to no heat anywhere, and cold showers are no fun at 5"30 AM.