It sucks to say it but I don't think COIN will get approval. The Winklevoss twins haven't had success and it's been over three years now. At this point I don't think it's Bitcoin related but rather how the structure of their ETF that is holding up the SEC.
SolidX has a better chance than COIN in my honest opinion. GBTC has the best chance of being approved with their background, capability and proven ability. Although an ETF is completely different than GBTC, in the eyes of the SEC, the track record is very important.
I hope I'm wrong and COIN gets approval. If not I'm confident we'll have a Bitcoin ETF by year end 2018.