Just came back from a week in Jan's splendid loft apartment. We found the flat just as described, bright, clean and comfortable. Quiet bedroom, big lounge and eating area. Wi-Fi works like a dream. Within walking distance to the main museums and within 10-15 mins by tram to the RAI Conference centre (if like us) you're on a business trip.
We didn't meet Jan, but he had left instructions which were more than enough to get us started in Amsterdam. We enjoyed some of the good restaurants he had suggested.
Highly recommended.