A lot of access control can now be installed right at each door. Paxton being one Harmon being another. Rosslare on the other hand on the backboard (along with a bunch more).
Our company likes to use Axis. They are POE powered manage 2 doors per box. I think there are docs that also mention that these can be mounted near the doors. Personally I like things centrally accessed rather then search through the ceiling tiles, but maybe because I'm used to doing it that way.
I can look at those other systems, but our company seems to be set on Axis, I think primarily because it is has a built-in web browser, IE, no software to install.
I too like to mount them in a central location. Much easier for power and a ups. I have never mounted them by the doors. I will have to take a look at the Axis system