The primary difference between the PSA and BGS graded Wrestling All Stars is the BGS graded example has very little lower border and would be off centered top to bottom significantly.
There are a ton of high grade BGS cards that have almost no lower border and these have zero chance of crossing to PSA in the same grade.
The BGS 9.5 in the EBAY listing would be a PSA 7 or a PSA 9 OC.
That is why there are so many more with such high grades from BGS relative to the number submitted.
There are plenty of great looking cards in BGS holders but in most cases a Gem Mint PSA graded card is stronger.
I have purchased a number of BGS graded cards and have had some luck for sure. The problem is my cross rate has been less then 40% and this is trying in many cases first in the holder and second out of the holder.