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.
Im avoided coinbase based on years of complaints and weak support commonly complained on this forum. I`m aware bitstamps long standing reputation in the past as one of the oldest exchanges to be around still, but I dont know if any US customers experiences so if anyone would like to share their recent experience that would be great.
Update: So CoinMama got back to me yesterday this message:
"Thanks! I've confirmed your wallet address. The order is now processing, and your coins will be sent shortly.
Keep in mind that once we confirm the payment the rate is locked, we do apologize for our response times, we are experiencing a high amount of traffic, but you are correct and we are working hard on a live chat option!"
The only reconsidered part in this situation is the rates are locked so you get what you paid for, so if you are not in a rush with coins then consider them, but downside to this is wallet confirmations are a hit or miss since apparently this is my first experience semi large amount of $500. I would send small purchases to see the wallet confirmation is responding to get your coins first before you take your initial purchase.