Overall I had a somewhat neutral to slightly negative experience. The biggest negatives were: their lack of communication - I had roommates and we repeatedly had to tell them they needed to email all of us for maintenance and other reasons to enter the apartment. (Our busy school/work schedules meant we would regularly go a few days without talking to one another). They even sent people to view our house without warninging us and then never bothered to show up.
Additionally, some maintenance was never performed to a satisfactory degree. We had issues with leaking and they came out 2-3x to try and fix it but failed to ever solve the issue. By the time we left the paint was flaking off of the ceiling due to the leak - in fairness, however, the leak was in my roommate's room and I don't know that they were very persistent in contacting BCH to fix the issue. Finally and most notably, the few times we had to call for maintenance for clogged plumbing, etc. their prices were astronomical. We had to contact them to fix a clogged sink and they charged us over $200 to snake it.
My final complaint would just be that it was clear the architect and/or contractors they used on the building were shoddy. Our apartment was less than 5 years old when we moved in, yet there were leaks from the skylight not being sealed properly and the AC collecting condensation instead of draining it. Additionally, corners were cut for no apparent reason and there was a clear lack of forethought in a lot of the design choices - for example, the tops of all the doors were unsanded and unpainted making them impossible to clean, the 2nd floor bath was made with poured concrete that was not only a huge pain to clean but quickly started cracking under its own weight, and they only used 2 thermostats on a 4 floor apartment leaving two floors perpetually hotter/colder than they should be because the thermostats weren't monitoring their temperature.
The few positive notes I can give are that they were always responsive when we contacted them, and they didn't increase our rent significantly while we were there.