I like the standard 2 mon poles. My eye level is right at the place where the bottom and top meet. My desk is a bit too short, so I put it on blocks. 
My bottom monitors are about 2 inches up from my desk. But I could raise them all because the top bracket to hold the top monitors are about 6-8 inches from the top of the pole with my 19" monitors. I like the Ergotron stands, just wish we had some economy of scale so they were priced lower. IIRC the price of three dual mon stands was about the same as one of the monitors I bought.

My bottom monitors are about 2 inches up from my desk. But I could raise them all because the top bracket to hold the top monitors are about 6-8 inches from the top of the pole with my 19" monitors. I like the Ergotron stands, just wish we had some economy of scale so they were priced lower. IIRC the price of three dual mon stands was about the same as one of the monitors I bought.