I just got a DVD burner (DVR-109) which supports both DVD-R "dual layer" and DVD+R "double-layer". My questions... 1. Can a stand-alone DVD player which can play both DVD-R and DVD+R discs typically also play the dual/double layer versions? 2. Does one (dual or double) have an advantage over the other? 3. Can someone recommend a reliable brand of media? I'd like to avoid turning these expensive discs into coasters. Thanks!