The price he paid was his country, his culture, his way of life, his language, and maybe even his religion in the long run.
The gift to America is immeasurable.
Cultural traditions can often be preserved within an assimilatd context, with some glaring exceptions which conflict with the laws of the land. In the event that is the case, perhaps the emmigrants would best settle somewhere more amenable to their traditions, rather than expect an entire nation to change to suit them.
In general, I take people on a case by case basis, and have met good folks, real jerks, and folks I do not know well enough to formulate an opinion of, in all sizes, shapes and colors.
It is the fruits of their labors, or sometimes, just their labors which speak volumes about their character, not superficialities.