I think HitBTC is the first exchange to go if you think there is something fishy going on regarding price manipulation... A lot of wallets in HitBTC have been disabled for quite a while already. Late last year when there was doubt about price manipulation in HitBTC, some people tried quickly move their coins between exchanges due to exchange rate climbing sevenfold. This eventually caused whole HitBTC backend to crash due to overload and they were forced to publicly display announcement whenever one or more of their wallets are going to be disabled for longer than few hours.
Yes I remember that as well. Right now Bithumb seems to be most wild exchange out there in terms of prices. Though Huobi is now seeing major premium over there as well. Wallets hopefully come back up soon.
I haven't used Bithumb yet... I usually use the exchanges that have more than one interesting coin and least amount of negative comments. I used HitBTC only because of the Dashcoin network split and MinerGate being on same side of the split as HitBTC. Had to use MinerGate on my laptop because better mining software don't work with 32-bit Windows...
Being in the US, I am mostly limited to the bittrex's, poloniex's, coinbase's, gemini's, kraken's and binance's of the world. :)
As a coin developer I follow all exchanges that are not already marked as insecure. If exchange shuts down too many user accounts, I stop following and using it...