I really enjoyed my stay as a solo traveller even though the rooms were small. Breakfast was delicious and the snacks throughout the day were perfect (think cheese, baked goods, unlimited coffee, drinks and charcuterie). I ended up doing quite a few day trips from Amsterdam to Utrecht, Zaans Schans and having a delicious breakfast to start my day was the best.
PROS: Staff are super friendly, welcoming and breakfast/snacks throughout the day were perfect. The area was also really quiet and safe at night. Convenient to get anywhere in the city and to take day trips from.
CONS: Room was really small (manageable for a solo traveller) and the shower situation is a bit iffy. The shower curtains also smell so strongly of mildew, even though I could tell the cleaners did their best to tidy up each day. I also had a large suitcase because Amsterdam was the last leg of my 2-week trip and it was a bit hard to maneuver inside the room and up the stairs past the elevators.