Meh, they'll both have 10's of mils in the bank, huge houses, the cars they want already, a couple years at 5mil a year ain't half bad, but realistically, they'd still have to retire, and the money they have can be invested to return 10's of mil's over the rest of their lives anyway so its hardly going to make or break them.
I'd think realistically playing in that heat would be horrible, long hot very tiring training sessions and worse for matches, in a league no one cars about.
MLS is FAR more appealing, better life for their kids/families, better places to live, a 1-2 hour flight from every kind of weather/location you want, a league that at least some people care about that is actually improving pretty dramatically, for similar money. I know which I'd choose.