I also decided to re-read "The Witcher" series in preparation to The Witcher 3: Wild Hunt game. I've read this book series back in high school and I remembered only that it was "fun". Reading it again after so many years... I find it exceptional. One of the best book series I've ever read (fantasy or otherwise) miles ahead of "A Song of Ice and Fire". It shows that you can build rich, convincing, interesting world without a ton of "fat" in the form of pointless story threads. If you're at all interested in fantasy literature give this series a chance. You won't regret it (unless English version of the series is poorly translated but I've read some of it and it seems fine), Oh and btw Witcher 3 game writing is not as good as in the books but good enough to give them justice and I find the game exceptional as well.
I remember, when I was reading Witcher for 1st time, I did it in one week (book1-1day, book2-1day, book3-1day, book4-2days book5-2days). Witcher is epic fantasy saga. Definitely worth to read!
btw: There is also new book from Andrzej Sapkowsky about Geralt from this year.