I always feel far, far safer as both a buyer and seller on the MM than I do with random eBay sellers.The Members Market is overrated. If anything people actually want is advertised at a price cheaper than the bay, some lurker snags it instantly.
As a seller, the MM is regulated tighter than a duck's butt. Adding some additional info to my one and only selling listing on the MM (for a GPU and CPU) resulted in me getting suspended from that board for bumping, even though my post from like 45 mins before was already right at the top.
I also advertised my hardware on the bay and it sold BIN for more (even after fees) within 72 hours than I was asking for on the MM here, where I got zero interest and one suspension for my effort.
You're really not missing out on anything by not having access to the MM.
Sure as an eBay buyer refunds are easy. But I tend to find items not as described and the seller not interested unless I open a case.
As a seller I feel less likely to get scammed on the MM. Personally I like the MM.