I'm a huge Bill Malone and Tommy Wonder fan and I have both On The Loose & Visions of Wonder, LOVE them both for different reasons.
If you're more into cards then you should really consider purchasing On The Loose, however, it isn't for beginners but it's full of great material.
Tommy presents some really strong card magic in Visions of Wonder as well, but he also has several other effects that have nothing to do with cards.
In my opinion Malone is the better teacher, as it's one-on-one during the explanations, whereas Wonder is accompanied by Max Maven (off and on depending on the trick) and you get to watch as Tommy explains it to him which gives it a more "fly on the wall" feel.
You can't go wrong with either, their insight into magical theory makes it worth the $ alone.