This is not too bad as a language course, but it has some weak points, such as very confusing gender hints. Instead of indicating whether you are supposed to write sentences as a man or a woman by writing "male"/"female" it switches between "woman"/"she", "man"/"he", which is really confusing sometimes since the gender of the person you are speaking to also affects the verbs and whatnot. Why not just put "I (f) will call you (m) tomorrow"??
At least there's no "How to buy your woman a drink in Polish" part, which I once encountered in (I believe) the Hungarian Assimil... Like all language books, this one does assume the learner is a man, but it does it in a less obvious way.
The audio is also extremely annoying since every track starts with like 15 seconds of blabbering in English, which is absolutely unnecessary. I would have listened to the audio much more if it weren't for the English taking up so much time.
All in all, a decent introduction to Polish. For learners lacking understanding of Slavic grammar it may be a bit difficult though, if you don't repeat the units a lot. It just throws the grammar at you, gives you five sentences to practice with, and moves on. Already knowing at least one Slavic language helps considerably. (Unless that language is like... Bulgarian.)