I can't say if Luis is a good or bad host because I've never met him. I took the keys at the desk of the residence and I returned them in the same way.
But I can say that it's quite easy comunicate with him; when I asked him something he replied to me in a few hours.
The location is good. The neighborhood is quite and safe and it's really simple to reach it by metro.
We found the apartment not really clean, especially about bed (bed sheet with black spot) and bathroom (shower curtain's seen better days).
The swimming pool on the top of the residence is really nice and, if the weather is good, it's possible to have a beautiful belvedere on Santiago.