is not a waste of money. I have three of them, two Samsungs and a Philips. They play perfectly and take up half the space of two units. But I didn't buy them to copy. Each unit has software/firmware that will prevent copying commercial tapes/DVDs. At least in any quality that would be viewable.
When I want to copy something I can't live without, I connect my USB video capture device to my PC, connect my VCR or satellite output to the capture device, record to my HD, use software to convert it and then burn it to DVD. But it's a royal PITA. Too much trouble and time. For me.
Just remember this. When you copy any media with an analog portion, it'll look like crap compared to a commercial DVD or VHS tape. If you have home movies and want to archive them to DVD, go for it by all means. The jury is still out on which lasts longer in storage, with the slight edge going to tape.
Wayne