I use Middle Atantic Too
I have two 7 foot Middle Atantic racks in my theater that are the AXIS variety thus they pull out. I would rather have easy access to the back of the racks but that wasn't possible in my new theater thus the pull out.
The advantage of rack mounting is you can get more gear, more neatly installed with no cable clutter or BS.
The downside is that you need custom rack shelves for new gear and it is a pain to swap gear in and out.
In the end - your system should look like the insetment it is thus rack mounting your gear is a good solution for many of us with complex systems.
Jerry Del Colliano