I dealt exclusively with Godfried, and he responded with impressive speed. The only thing that was problematic was the wifi connection, something I really required particularly as the sim card I'd bought didn't allow me to connect with data for the first day or so. He found a different way in which I could connect, for which I was really grateful, and then his second important bit of advice (to unplug the router from the wall and let it start up again) was all that was needed to get properly connected.
As for the place itself, it was very comfortable. It's in the heart of Brussels, very very close to the central square, and surrounded by bars and cafes and restaurants. So you might think that it's a bit on the noisy side. NOT AT ALL....it was actually incredibly peaceful there, mostly because there's a building between the apartment and the street. So you're right in the midst of things, but in an oasis of calm.
Everything worked as it should, and I'd definitely go back there again!