Not so, Segregated Witness adoption pushed it from $4 to about $15.

The whole Bitfinex scandal could have contributed to the rise as well. Bitfinex was one of the largest exchanges, but now no one (except people with Taiwanese bank accounts) can wire fiat out. Suddenly, traders are pouring out of Bitfinex and into the next best place---Coinbase, where trading on margin is free.

Really, the only reason not to use Coinbase right now is if you think that US banks will "crack down" on them as well and not accept any transfers out.