It's very difficult to get an impartial opinion on this, because whichever forum you're in, naturally the gurus are going to push for their materials (as will their disciples).
I'm a member of several forums, and generally you'll hear a lot of noise about gurus from other companies "having no game" or being "fake" and all the rest of it.
As this is a UK based site, it's natural that a great many US based PUAS are going to get some slack (I read that Style and Janka have no game somewhere in this post. Sorry, but bullshit).
It is generally accepted that David DeAngelo's double your dating is a good place to start, and a lot of neutral PUA review websites recommend it.
Two other books which are very highly rated both claim to supersede the original "Mystery Method" (Mystery); They are "Revelations" (Mystery, Matador) and "Magic Bullets" (Savoy). However, both of them are incredibly expensive and Savoy's love systems company has become a bit of a Mc.Donald's chain (much like RSD), and it just seems that every time you use their forum, website or (according to a friend) even if you buy something from them, they are CONSTANTLY trying to sell you something else. That said, most non-affiliated PUA rating sites rate them both very highly. Then again, "Mystery Method" won't even set you back a tenner, the others come at a hefty price.
With regards Style, his book "the Game" is enjoyable and engaging, but do remember that is primarily a biography. It is not a self-help book or PUA manual. I would recommend it though, as it is well written and a great story. His forum is probably one of the best US based forums too.
Paul Jankas short 17 page pdf getting laid in New York was one of the best I've read actually. Sometimes keeping it short and sweet works best. It's free as well so google it.
I've just started reading "Models" as I'd heard good things about it. I'm liking it so far
