I wouldn't short bitcoin, I do wonder why peeps need to trade Bitcoin futures on margin?...... Like Bitcoin isn't volatile enough? We need to trade that puppy on margin? Lol!
PS: I saw interactive brokers CEO on CNBC say bitcoin could go to $100,000 before it crashes to "NOTHING"!
PPS: I think the safest way to play bitcoin is the Bitcoin investment trust GBTC or SANP.