I am preparing a fresh rerun of the entire series very soon. So far got 80 hours on Witcher 1, 110 on Witcher 2 and 130 on Witcher 3. Been a while since I last played so it's time my favourite series is given another rerun.
I can definitely tell you that any money spent on the Witcher 3 is money well spent. It's absolutely amazing and the DLC are just as good (and almost as long) as the main game!