A friend of mine works in London as a broker, and is paid in $. During the last year he has taken a bad hit on his income.
I would definitely not want to be paid in US$ right now.
It's a bad question though because it specifies none of the other factors that are important. I'd much rather be paid a million dollars than a thousand euros, for instance.
Gold $1 coins taxed at face value.
"It depends", obviously. Please fix the question if you want a serious answer.