I bought the DVD and a complete set of RG Veda manga. It is my favorite manga from the CLAMP.
What on the DVD is based on 1992's OAV. Technically speaking it is not superbly done not like all digital enhanced ones. However, the two episodes in the set do reflect the great art work in the manga. In my opinion, the best image in the DVD set is short lived King Ashura (well, he is really sexy :) ). Yasha's image is a bit dull. He had a much better image in the manga.
I showed somebody in my family who had not read the manga, the person liked the show just by looking at the art work and listening to the music. Well, the person is usaully very picky on what DVDs I should buy or should not. Certainly, I had to answer some "why"s and "how come"s after the show. The conclusion was "This one is not bad". Thanks, sweetie.
It is your choice whether you should buy the DVD. To be honest, without the manga, you may miss many emotions. The emotions are a CLAMP's manga all about besides their incompitible art works. Oh, by the way, the English voice acting is not bad at all.