I must say, I am a BIG fan of David Deangelo. I like the way he teaches and he is spot on in most of it. I think he deals with INNER game very well. His advanced series is amazing IMO and well worth it. The DVD's are much better. I'm NOT a big fan of his Interview series however or his sexual communication series. I haven't listened to the mastery series yet, but I'll get around to it. I was very unhappy to learn that Mystery's performance was mostly cut although he does get a fair bit of time all the same. His ****y comedy series is great too.
However, deangelo's teachings are primarily to GET PEOPLE LAID QUICKLY. His number close technique (which has been copied here - "Are you single?"), I am not a big fan of. I think for approaching women and building VALUE, Deangelo sucks. Why? Because he teaches guys NOT to have a higher value when approaching. He teaches them to get the email and build their value over the emails b/c he assumes they can't approach and build value on the approach. This obviously leads to a great deal of flakes and a great deal of ***** shields and a great deal of embarrassment (But who gives a sh*t anyway!). I DO think his style of approaching is bad and I don't like to read people on here doing it.
So for actual approaches, Deangelo is great at the underlying theory and the inner game, but extremely poor at the approach.
Vitalio on the other hand has a good 3 books dealing with everything from picking up women to getting the perfect body but it's nothing you wouldn't have read already. I got them and it was more of a revision for me than anything.
Wow, I've rambled here. Apologies.