amd64 or i386 for desktop use?

[RW]

On Wed, 5 Mar 2008 19:47:53 +0100 (CET)
Wojciech Puchar <wojtek at wojtek.tensor.gdynia.pl> wrote:

> >> of RAM, and I seldom use more than half of that. Mind you, I'm
> >> using a simple window manager not a desktop environment with lots
> >> of bells & whistles.
> >>
> >> I suspect binaries on i386 will be somewhat smaller. But amd64 has
> >> more registers which might give some speed advantages. I haven't
> >> tested it, but
> 
> yes it is much faster (somehow like 20%), and code size are rarely
> big part of memory usage. 

Everything I've every seen about this suggests that amd64 is faster on
a few applications, such as mp3 encoding, but generally there is very
little difference, on average, across desktop applications. Do you have
any measurements to support that 20% figure.