From our experience, we only recommend trading on the following exchanges:
Bitcoin Futures Bitmex (http://bitmex.whalepool.io/) - Proven track record, available in the whalepool telegram chat also. A great platform with high leverage available
Altcoins Binance (http://binance.whalepool.io/) - A new comer to the altcoin scene rapidly gaining popularity for shitcoins. Run & administered by the ex-Okcoin CTO. Seems very popular with a better UI & selection than bittrex
Spot Trading BTC/Alts Bitfinex (http://bitfinex.whalepool.io/) - Proven track record. Great staff. The most liquid BTCUSD market. Find Bitfinex reps on teamspeak also.
Bitcoin Options Deribit (http://derbit.whalepool.io/) - A newcomer to the scene but growing rapidly. Used by Whalepool users for some time now as the prefered way to trade bitcoin options. Ask Saj any question in telegram.
Forex/Commodity/Stocks 1broker (http://1broker.whalepool.io/) - Without a doubt, the cheapest & best CFD platform to use with your bitcoin. Including copy trade features. Proven track record. 1broker reps also available on teamspeak
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The above references an opinion and is for information purposes only. It is not intended to be investment advice. Seek a duly licensed professional for investment advice.