AdSense is a Google property. That implies that so long as you play by the guidelines, which you could be safe and secure together with your advertising. You don’t ought to worry a couple of glitch in the system inflicting your site to drop in search ratings. Other choices, like Infolinks and Clicksor, have somewhat more poor reputations. They aren’t, in and of themselves, hazardous in your site.
However, because they are not as carefully monitored as AdSense, they’re easier to use in black hat fashions. This in turn means that Google might be more prone to scrutinize any mistake you make and potentially count them in opposition t you.