it depends on what you mean by "well", there are many aspects, like measuring "success in life", it's a complicated topic.
There are graphs on how many refugees are on welfare, it's pretty high, it was floating around somewhere. Most are on welfare for at least short period of time because when you get to the country with literally shirt on your back and empty pocket, getting a job still takes a week or two at the fastest.
I can offer my own, extensive but yet anecdotal observations about "success". For older people it's pretty hard to adapt and learn culture/laws. It also depends heavily if person arrives into a big city where there is an ethnic community. That's the worst scenario because most communities give absolutely no reason to learn English or culture. If refugees arrives into some bumpfuck place, adaptation is pretty rapid, but it hurts like mofo because there is no one to talk to in your language (at least in pre-internet days), depression, alienation etc. but in the end people have to adapt and learn.
First gens is a 50/50, it depends what parents speak at home and I've seen kids lag in language skills because they speak native lang at home. Discipline is usually pretty good though.
A lot of refugees do well not for some freedomic reasons but because threshold of pain is very low and consumerism is low as well, plus a lot emphasis is placed on discipline and traditional values like education (speaking for Eastern Euro xpats, 3rd world trash isn't buying books).