Primers under Makeup

I have to admit I didn’t even know these existed, and I’ve been playing with makeup since I was 13.  I have very oily skin in the T range, and this might be something that would discourage the early afternoon glare off of my face.  I think I’ll get a sample and give it a try.  Have any of you used primers effectively?

http://www.everydayhealth.com/blogs/drwusskinandbeautyblog/are-makeup-primers-necessary?xid=nl_EverydayHealthSkinandBeauty_20090812