My girlfriend and I stayed for 5 days at this apartment and we really enjoyed the stay. The interior is wonderful especially the bathroom. Gabi helps you if you have questions about anything and tries to answer as fast as possible.
The flat is located about 13 minutes away from the centre and 14 minutes away from the railway station "Brussels Zuid/Midi".
Consider that the staircase is narrow so you might need help if you are not so fit to carry your luckage for 2 floors.
All in all I would recommend this apartment if you want to spend a wonderful time in Brussel/Belgium :)