Sex advice DvD's

I'm not normally one to turn to videos and help for advice bust with todays new addition I have been tempted. Today a tantric sex DvD surfaced, this is a grey area for some people and an area I wish to explore more. I've looked into areas of tantric before and some books aren't actually about the life style or act but more of personal opinion.

For someone who has never used a self-help, tips, or fact sex video; I am wondering what it is like.

Do people find these better than books?

Do they offer advice like promised rather than just being a sleezy video?

are they filmed correctly?

There are many points I wonder about these types of DvD's, some are similar to my doubts in certain written texts and spoke advice as well.

What are your experiences?