We celebrated my birthday on the boat with 16 guests, the boat is really well maintained and the common area is very cosy and the kitchen really well equipped with everything you need to cook for big groups. The boat was extremely well prepared and clean. Grietje communicated very well with us and was always available and friendly when we had questions. NDSM area is great, there are a few nice restaurants/
Club such as Pllek.
There are many options to reach the city centre like ferries but on weekends they are not super frequent, you also have bus.
It would be great if the boat could be in the city centre but if you have time and willing to explore alternative districts it's a great place to have a big group. I would definitely recommend it again!