It was actually a BMXTRIX recommendation. He factored in cost, quality of fasteners and ease of installation based on what his guys ran into durring installations in the field with different applications (I think). He's actually a big fan of Monoprice (this I know). Maybe at the time he just had not tried their mounts or maybe the Peerless fastener package was better quality and more geared toward various applications.
During an install all you need is for some cheap fastener to break and send you to the hardware store effectively doubling your time because of a 9 cent screw. The Peerless mount I got was $67 I believe from the source he linked. That was a huge savings for me over a $200 Sanus mount. I'm not sure that I would hang my beloved Panasonic off a $25 mount never mind a Pioneer.
The way I have mine installed you could do chin ups on it.