Well as mentioned before, what diff does it make? Xbox software is designed to run perfectly on a 700Mhz. So, unless you're writing a homebrew rip-off version of Maya, SETI signal analyzers, or software to predict Earthquakes, it won't make any difference.
Cool that the mod worked, but it's impractical, so i doubt anyone would sell it (unless, of course, people are dumb enough to buy it).