Yes they do. The only difference is that visitors have to click the ad units first and then the ads that will display in order for the publisher to earn.
they do work, and give you good revenue if your niche is good. but you have to place them in the rightly.
I earn the majority of my revenue from link units. I also have a very targeted audience, so results would be a lot worse with low-quality traffic.
Yes they do. in one of my sites i earn most from linkunits. It depends on the site, just try it for a few weeks and see if you get better or worse results.
what if i place 728x60 size normal ad instead of link units? which gets more clicks or revenue? i assume that users had to click twice for link units to work.
dude it depends on the placement of the ads on the page. both of them are good for revenue generation