Might I suggest something a little different. It depends, of course, on why you wish to study Latin. If for school work, then one of the two books you listed would be best. However, if (like me) you are studying as a hobby, then 'Learn Latin', by Peter Jones is a great and inexpensive introduction to the language. It teaches you, in fun, easy steps just enough (and no more!) to read excerpts from Catullus, some bible stuff, and parts of the Bayeux tapestry.
It covers quite a lot of the language, albeit superficially (the subjunctive takes only 4 pages), but having read the book, and done the exercises, as you progress through a more advanced course there's less feeling of 'omigod what's this?' than would otherwise be the case.
Just my 2 cents worth (which at current exchange rates is worth about 0.6 cents)