I've got 22 DVD's from chessbase, thats including the ones made by Gary Kasparov. tbh I can't really fault any of them, if your wanting to learn the Ruy Lopez I'd much prefer watching the dvd of it than reading it in a book, so it really depends on what your after.
What I will say though, alot of the newer DVD's have the games preloaded, that is to say that the person taking you through the game doesn't need to read notes etc because the game data is already there. This I found slightly annoying because now they tend to zip through some moves whereas before they took a little bit more time. This is especially the case with the endgame discs, however I can understand that more due to the number of variations etc. But the German guy does tend to talk a little fast.
For myself I've never really studied endgames, sure I can win rook vs King and other simple things like that however I didn't really know the basics such as with rook vs king deal with making a square each move reducing the square where the king can go, likewise with passed pawns, make a square with them if the king is in that square it can capture the pawn. So it's given me a better understanding of the endgame and making my moves more efficient.
btw I may be selling about 10 of my DVD's on ebay thought I'd make it a joblot rather than sell them separate so if there is anyone here interested feel free to pm me for details