Dvd+r discs better for data then dvd-r?



I encountered a weird problem a couple of days ago, i was moving around 30 game cds over to dvd-r, but had problems with nero burning 2 of the 4 dvds. One dvd had more then 8 directories within each other so i had to use relaxed ISO9660 settings. I when to burned the disk on a dvd-r nero would start to write the disk, then it would say write failed. I took the disk out and tired again, same thing. Tried another dvd-r and it still wouldn’t burn it. I thought i maybe i had bad media so i tired burning the games to a dvd+r and that worked fine. I then tried burning the next disk on the dvd-r media, this time i didn’t have to use relaxed ISO9660 setting and the disk burned fine, then next disk did have to use relaxed settings and it wouldn’t burn on DVD-r either, but it would on DVD+R.

Is this a known limitation of dvd-r or is nero just being picky?