I use spun content on blog networks for a long time already, i did not lose serps, in fact i managed to rank super competitive keywords all the way to the top in Google with it.
Just do not use auto spin garbage, even "spun" content can look good.

Edit: If you use "obviously spun" content it's your own fault..if i want an article for blog networks i am usually taking my time to make a "good" spun article..it doesn't matter if it takes me an hour to make it since i can use it many times.

Suggestion: It depends on how much important the keyword is.

If it's a gold-mine keyword which can bring you hundreds of thousands someday, you should invest on unique content

If it's just another microniche keyword which will make you a couple of bucks, go for spun content

Suggestion 2: Don't use one single spun article for more than 15 times!!!

Spun content still works well, you will have to spun it well.

If your spun content is more than 70-80% then its fine

Yeah just use well spun content and you will be fine.

Google will not penalize you the quality of content on another person's site. I would never use crappy spun content on my own site, but I'm a HUGE supporter of spinning content on blog networks or web 2.0 sites.

Making it readable is also a good idea. So you are stepping in the right direction. The problem with unreadable spun content is that it can be reported and taken down. Which means that you are only creating temporary authority that can be yanked at any moment.

Create spun variations that make sense, and you can create a bunch of link juice that will permanently flow towards your money site.

If you have 1000+ words article, then max you should spin it 20 times, preferably manually, this way you will get max results from your spun content.