The first thing anyone considering Alexander's place should know is that because it is so close to the subway U3 line you can get to anywhere in Vienna quickly, google maps makes it appear much further than it really is so do not let the perceived distance deter you.
The second and most important thing all travelers should know is that Alexander is probably one of the most amazing person you'll ever meet. He is extremely helpful and provides a wealth of information. His attention to detail is perfect. You owe it to yourself to stay here while in Vienna!