In the last nine months alone:
1. I bought a Scout knife that was represented as "very good condition" and "no cracks in scales." The pictures were backlit, but the seller had good FB record. When the knife arrived, all four "blades" were badly piitted and both scales had obvious cracks. The punch could only be opened by using a tool of some kind. When I politely asked the seller to take the item back, he told me it was sold "as is." That was incorrect both practically and legally since he made specific representations of condition that were clearly inaccurate. That is a sale by description, not "as is." After two months with no satisfaction, I had to resort to contesting the charge with Discover. He then gave me negative feedback.
2. I bought a Cub Scout knife that was represented as "both locks work well." Pictures simply do not tell you if that is true. On arrival, neither lock worked at all. For what followed, see above.
3. I bought a Scout knife that was represented as "excellent." The pictures were cloudy, but the seller had a good FB record. On arrival, all four blades were rusted shut. After the seller ignored my request to reverse the tranasaction, I simply gave up. He did not give me feedback of any kind.
I each case, I paid within one hour of "winning" the auction. I usually do better than that.
In each case, eBay would do nothing.
I would NEVER buy a folding knife on eBay unless: a) the seller has a 99.9% FB record or better; b) payment by credit card is allowed; c) the knife is new.
I have puchased fixed-blade knives on eBay that were misrepresented as to condition and even length (by 1"), and the sellers would not take the items back. However, by the nature of the items (no working parts), you can better protect yourself.
While I have no doubt that there are dishonest buyers who resort to eBay, there are sellers on eBay, enabled by eBay/PayPal, who make the place a stench in the nostrils of honest men. The misrepresentations are rampant.
I have never had a problem of any kind with a purchase from BF or the other place.