I voted for "well off". Why? Well, despite the OP assertion that he meant "middle class in repressive society or poor in a free one", I think you have to do opposites. The opposite of poor is not middle class, it's rich. So, I assumed rich.
So, the question becomes would you rather be poor (homeless and hungry) in America, or rich (mansion, power, parties with bureaucrats) in China/USSR/North Korea? Given that the rich don't have to play by the same rules as everyone else (this concept is true, regardless of the country), then I'd much rather be rich in a society that oppresses everyone else.