[trevord92]

Personally, a book holds more value (even if I don't actually read it)

Positioning is everything.

A "free" book just for the price of shipping and handling is still an option.

A paid-for book works - just skimmed the "look inside" of a £25 book on Amazon that had free links to both audios and videos that near enough covered the book's contents. So even though I didn't buy, I'm on their email list.

Audios turned into podcasts.

The options go on and on.

Which I suppose is a long-winded way of saying go with what your gut tells you to do. Or even (time permitting) do more than one of the things you're considering!