The stay in unit 6 of the Gran Maison was absolutely incredible - the location and people-watching cannot be beat.
Note that there are about 5 half-flights of stairs up and down to get to the unit. Definitely wouldn't recommend for anybody with mobility issues. It's an historic building, so stairs are narrow and frequent!
My partner and I entered departed Brussels from two different train stations (Midi and Centraal). This location was close to the tram stop from the Midi station, and a 5 minute walk from the Centraal station. Both were very manageable with suitcases.
Would highly recommend this location for anyone wanting to stay centrally in Brussels!