Cash always. So long as you don't need to bet x amount of dollars before you can pull it out. Otherwise I'd take the spins, again with the idea of if you win you can immediately withdraw. Goal is to get free money out if at all possible.
Possible or let's say there is a potential that you will win in a free spin but in cash, you will always think to withdraw the money that is why possible you will not gamble it just withdraw and keep the money. You will never know in a free spin you will become a millionaire once you will hit the jackpot prize.
So that is why I prefer the free spin though the majority is cash money.