PoS/Masternode (instantx) networks are the future IMO...
"Amid a surge in mainstream media interest, not to mention projects raising funds via initial coin offerings (ICOs), transaction backlogs were visible on the network. Data from ethereum information provider Etherscan shows that more than 300,000 transactions were broadcast on 20th June, the highest amount ever observed on the two-year-old blockchain."
"The rise in activity has also pushed the size of ethereum's transaction blocks – which change dynamically – to new highs, while the amount of gas used to send transactions, a kind of charge for processing power, has climbed to new heights as well."
"Combined, these changes appear to be impacting businesses."
"The list of exchanges that have announced withdrawal pauses or service disruptions in the past day includes Bitfinex, BTC-e, CEX.io and ShapeShift, among others. Social media posts suggest that users are also seeing disruptions when using other exchanges, including Coinbase, BitBay and Poloniex."