Is 3-pass encoding worth it?

[FAII]

I'm currently encoding all of my iPod-compatible videos into 320xXXX videos with a 400 kbps bitrate for video and 96 LC-AAC birate for audio using 2 passes.

I have yet to try 3 passes, but my friend tells me that you don't really need it. My question is: Is it worth it?

Do you get noticably better image quality? Is it better at all? Will the file size just decrease slightly?

[foxyshadis]

3-pass just juggles the artifacts around to distribute them more uniformly, really. It doesn't (normally) add quality in any way, aside from the warm and fuzzies of uniformity. In the vast majority of circumstances it should make no perceptible difference from 2-pass.

But don't let me dissuade you from testing to see if your situation is helped.