Google is getting VERY good at catching spun content so you'd better be talented at manual spins. If they DO catch you, of course they'll spank you... and hard. So anything you use spun content on is inherently AT RISK. Worse yet... Google gets better at finding spun/poor content every year. So in the longrun you're screwed. I'd weight your other options and see if you couldn't find a cheaper source for manually hand written content.
WordAI is probably the most famous content spinning service. Many people swear by it and the quality of the content it produces and it is not empty talk. But let’s see how it will spin my short story. WordAI has two modes of spinning – “Standard” and “Turing”, with the latter being the one that produces better results. I will spin the text with both of them.
He saw a trainer nearby and asked why these animals just stood there and made no attempt to get away. “Well,” trainer said, “when they are very young and much smaller we use the same size rope to tie them and, at that age, it’s enough to hold them. As they grow up, they are conditioned to believe they cannot break away. They believe the rope can still hold them, so they never try to break free.”