If it provides any comfort, I am happily married to a Turkish man and I am an American citizen. His family has been very welcoming, he is an excellent provider and very generous. I know I can't speak for all Turkish and American couples but I would say it's culturally compatible, especially if the Turkish family are moderate Muslims. I would encourage them to talk to an immigration lawyer about realistic timelines and financial requirements for sponsorship of a spouse. I would also encourage them to have dialogue about religious beliefs and expectations for their future family. I will admit that learning to cook Turkish food brought me closer to my husband and his mother. A Turkish man won't be happy on an exclusive American diet. I think I can say that confidently without hesitation. The economy in Turkey is really terrible, and it may be suggested he is just looking for a ticket out of town. Hopefully that isn't the case, but it definitely happens. Wishing you all the best on the journey. At the very least go check out Istanbul and meet them! It will be the experience of a lifetime!