I did a search on a bunch of threads here but still couldn't get a handle to my question. I want to do a back up to DVD's. The software that I'm going to use is Impressions. My computer is a new iSight iMac 20". I want to use RW's. Questions: Should I use + or - RW's. Also if I use Dual Layered DVD's, are the Dual Layer DVD's available in + and -. And what about the speeds. Is there such a thing as 8x DVD+RW DL ?? From what I've read so far, DVD- are the better way to go than the + formats because more DVD players will accept them, but as of now, that's not my concern being that I only want to use these for incremental backups. This all very confusing.......Any help to explain all this would be much appreciated.