2x4's or 2x2's for building benches?

[Reynolds]

I am going to be putting in some benches in my permanent this upcoming weekend and I am curious if I can get away with using 2x2's I'm thinking a guy should probably use 2x4's I am going with two benches benches on either side with a drop down table in the middle.

[McGurk]

If the span is going to be more than 32", I'd go with 2x4's, or 2x2's with a leg every 16". The exception would be if you are going to use 3/4" plywood, glued and screwed to the 2x2, and even that shouldn't exceed 4'. These are just guesses, though, as to what I'd do; but I am a notorious over-builder. I'm not a big fan of sagging.

[broman]

Take a look at this. This is the construction of my bench. Table spans the gap between the benches and gets placed on a pole.