I use a bp/w with the "deluxe" harness that is both adjustable and has pads. The pads are nice if you're walking for any distance on land before splashing (some shore dives). I'm using the diverite harness, and I often pick up the bp/w with an Worthington lp108 attached by one strap. I've never had a buckle break or come inadvertently unbuckled or loose. I did replace the harness after 5 years just out of an abundance of caution over the buckle breaking.
I also use an air2 with mine. As others have said, nothing about bp/w makes an air2 any different than with any other bcd.
I started with a steel plate, but have also bought an aluminum, and two plastic plates, and a freedom plate. The webbing is easy to move to different plates and I switch it up sometimes. I usually take the aluminum plate when I travel.
I've taken the b/pw (in checked bag) to Cozumel twice, and Roatan once. No problems with TSA or anyone else. I've usually got more expensive stuff to carry on (cameras, regulators, computers etc).
I use diverite ditchable weight pouches with mine. These also have never inadvertently come loose. I remove them after every dive, they're very simple and reliable.