Are these the kind of racquets that are really light where you have to provide your own power? Or are they the ones with the smaller frame? etc? I have a LM prestige mid right now and I'm assuming this is a "powerful" racquet which means that it's not as demanding as other racquets to play with....but isn't a heavier racquet probably harder to swing with/more stressful to play with???? I'm confused.