If you paid for your tapes it is OK to make a backup copie for personal use. John
I have made over 300 DVD using the DVD-R abd RW formats with virtually no problems. I use a Panasonic dvrhs2 primarily but also a DVD recorder on my computer and a DVD-R recorder on my TIVO.
I used a stand alone tape player hooked into my Panasonic through a SIMA copymaster to convert my tape collection to DVD with no problems.
You can not use the tape DVR combo units to convert commercial tapes to DVD because of copy protection. They work fine on your home video collection or stuff copied from TV. I paid for my tapes so I figure it is OK to convert them for personal use.