Have read the last three, I would say that The Black Company is the best of them, followed by Witcher and Lightbringer. Lightbringer is still not finished though you can postpone it after you read the other two.
All three of them are worth it though, really good sagas.
You definitely haven't considering that it is a new series (assuming that he is talking about Brent Weeks series)
Book 1 was weird but I loved the third one. For what is worth, the series changes a lot after the first three books. Book 3 and the last one being my favorites.
I have. The first book is amazing, the second one is decent and the final one is arguably the worst book I have ever read (and everyone who has read it hates it, its status in asoiaf forum is similar to Fellaini's status under Moyes here).
Either do not read it at all, or stop after the first one (it was meant to be a standalone either way, so it works by itself).