There have been reports of sites that were apparently penalized for participating in link farms. I say "apparently" because the SE rarely tells you anything, and, if they do, it's often in vague terms instead of, "we found linkpopscam.com pages on your site."
I would recommend steering clear of these programs. Beyond the potential danger if some SE decides the program is spam, it is almost certain that most of the links will be from sites with a theme unrelated to yours.
I'd suggest a targeted reciprocal link program - try to seek out sites with topics closely related to yours, preferably popular ones. Zeus software will automate some of the process, but you can certainly start off by identifying sites using the same search engines you are targeting.