Installing BAS harnesses in the front seats was the the first thing I did after buying each of my airplanes. I spent about $2,200 for each harness and another $500 or so for the installation. The Cessna 172N had only lap belts and I liked having the shoulder straps on an inertia reel for comfort and freedom while flying. That aircraft is now leased to a busy flight school and the BAS harnesses have held up well to hundreds of students and instructors. My Cherokee 6XT had a shoulder strap with an inertia reel but I wanted both shoulders secured.
For the C172 I chose the Standard buckle because that's what BAS said was the most popular. The shoulder straps are permanently attached to the lap belts. I really like this design. When I bought for the Piper I was surprised they didn't offered the Standard buckle; only the Utility buckle. The shoulder straps slip on to the tang of the lap belt. Frankly, I don't like the BAS Utility buckle. It's more trouble getting it connected and my front seat passengers struggle with the four separate straps. But, it's a small price and hassle to pay for having a four-point harness.
BAS provided excellent installation instructions. Both installations look like they are factory installed.
