Since the Dothans do a lot at a lower frequency, the FSB doesnt have to be as high to supply more memory bandwidth.
The P-Ms are powerhouses. I've seen overclocked P-Ms eat up FX-53s in benchmarks.
The downside is that you dont have very many motherboard options if you want to mount a P-M on a desktop mobo. In fact, you are limited to ASUS P4PXXX series mobos. This is largely due to the fact that ASUS is the only one that makes a skt479(P-M skt type) to skt478 convertor.
It can be tedious to set up for some due to the BIOS flashing required for the mobo to accept the convertor/new CPU.
But, if you can get through all that, and are able to overclock, you'll be sitting with a really powerful computer that doesnt produce much heat or take up much power