I just got my G1 a few days ago and am finding the need for an extra battery. An original Panasonic battery is over $50 at B&H but aftermarket ones are around $20 on ebay. Looking at the specs on the ebay ones, they are not the same specs as the original. The voltage is 7.4V rather than the original 7.2V. Is this safe? Is anyone using these cheaper batteries with good results? I sure don't want to ruin a new camera.