Not sure about other people, but I signed up for that site a couple of days ago and got the 5 free credits they offer and used them to spread them through a couple of auctions that were running to get the hang of it.
When I had the hang of it, I thought screw it and put $10 on it (10 credits), and made 10 multiple bids on a PS4 auction (0.01 to 0.10) and I actually won.
This is the auction that I won:
https://cryptobids.xyz/details/19260For some reason no one else thought of bidding 0.01
After the auction was over I got a notification on my auctions page to pay for it and set up the delivery address, aswell as an option to get the BTC value of the item instead of the item itself.
I actually preferred the BTC value, so I didn't have to pay customs and taxes to import it to my country (Brazil), which has huge import fees.
Here is their TX of the BTC prize:
https://blockchain.info/tx/6dc34c18214ee8e7e3323916dc0cc9ec42f18d95c8b6e9aa8eb5517d0e7bb2e9I don't know about anyone else's story, but I can say from my own experience that they're legit.