I make it a personal rule to only post affiliate links to services or products I use and that I would recommend anyways.
With this said, I've not had much success with them as many people see an affiliate link and try to avoid them or bypass the affiliation. There is even a browser add-on that does this automatically. So do not expect a high value on such links.
Did not work for me. Adsense made more money with no effort. My websites tend not to have many people looking to make purchase decisions (not talking about AdminEmpower here).