Looking for advice on decent 'lectric trimmers. Decent being light, good battery life, power. Hurt my lower back several weeks ago, nursed it back, and stupidly went ahead and solo'd a hedge. Back to square one. My wife has a lil black n decker trimmer. Its 20 volt battery and not real powerful, but it's soooo light. Anyways, any real world experienced suggestions? Thanks all!