I`ll be adding all the US services and options and write a detailed review after this CoinMama situation is resolved or not and update here.
I am not from US, but I know Coinbase is the most popular exchange there.
I was able to transfer money from US to Bitstamp several times in the past, about 3 years ago. I never had problems with that exchange at the time. I don't know their situation now, but they are one of the oldest exchanges around and I never had any problems with them.