Bottom line: how many people have been the victim of a double spend? I am not sure a case of a successful double spend exists post march 2013 fork. BTC is still better than fiat.
Actually, I saw 5 double spends yesterday, each roughly 6 blocks apart. Right now, there is one double spend within the last 500k transactions:
https://blockchain.info/double-spendsNo one cares if double spends happen to small transactions... but shit will hit the fan when a large transaction is double spent.