What a great experience! The location is right in the thick of the old town, a block from the castle. The street it's on has many great restaurants and a micro brewery plus it's steps away from Vrijdagmarkt, Groentemarkt and Korenmarkt, the three major squares in old town that have tons of restaurants and shops. The central train station is easily reachable by the tram line 1 from in front of the castle.
The apartment itself is modern and well designed, with a nice bathroom (shower only) and an efficient kitchen. Comfy bed as well. There was some noise from the bar across the canal but it didn't bother me and I'm a very light sleeper.
Last but not least, Nelson was the best host I've had. He was kind, communicative and went above and beyond to make sure I had a good stay. The hot water turned off at one point and he had it back on within ten minutes!
I highly recommend this apartment!