Dear reader,
I did stay 6 days at his place. It was great. Barcelona is great and so is Chris. Helpful, polite and open minded.
I did stay in my room a lot for private studies and found a quiet and relaxing environment. In case, I had a concern, Chris always tried to help.
For going out, you are in one of the best areas of Barcelona I guess. Maybe not because of clubs, but bars, restaurants and other places filled with live are very close.
My private bike did survive one night allone outside in front of his flat. And my rental bike survived the other 5 nights there after my private bike was stolen in front of the supermarket during daytime. So the area around Chris seems to be pretty safe :)