I suggest a digital multimeter - and not the kind made specifically for RC. Get a DMM from Radio Shack, Home Depot, Harbor Freight, or wherever for $10-$20. Add your own 20 ohm 2 watt load resistor from Radio Shack. This method will be no more expensive and much more useful and more accurate than an ESV. Search the old posts or check Red's site for more info. Use stackable banana plugs and you will only need to make two easy solder joints.