There are so few romanian learning resources for english speakers out there, but this method is by far the best. It is superior to "Teach Yourself Romanian" (which looks like a first draft for "Colloquial" by the same author Dennis Deletant). I found "Teach Yourself Romanian" confusing and full of mistakes, whereas "Colloquial Romanian" is a polished language method, with a strong emphasis on grammar - which is the only way one can seriously master a language.
Tapes are of a passable quality ("Teach Yourself" has a better tape).
The only major missing item is an English-Romanian glossary, which "Teach Yourself Romanian" has.