It all comes down to what you are into. I really enjoyed
420 Cafe. The Hot Chocolates with cream were awesome, and I'm a fan of the Neville's Haze and NYC Diesel they sell there. There's also a Volcano Vaporizer to use, and you can request a RooR bong with an ice catcher, both on the house if you are smoking their weed/hash and super clean.
I also went to a few places that sold really poorly grown cannabis. Don't be scared to go in a few and ask to see the strains. You can determine whether the quality is good enough for you.
You gotta try out some Amnesia Iceolator Dutch Hash from the
Amnesia Coffeeshop too. It's €35 per gram, but you can ask for less. I only get half a gram and put a tiny bit in the bowl on top of my herb, it's very potent and will keep you buzzed for a few hours.