Back when i first got my rush in July i tried THIS:
http://androidforums.com/rush-all-things-root/739747-mod-app-swap-external-sd-internal-mempry.html
and I hard-bricked two new rooted Rush phones. It very well might have been user error, since I'm new to Android phones. Good thing I learned my lesson, and my local Target had some younger guys working there that didn't give a shit what happened to the phone since I only had each one about 3 days so I got new ones lol.
Glad to say today I'm running KKE ROM 2.0 at 1.2 Mhz and it's blazing fast with no instability whatsoever.
Btw I'm running the Ext-Int swap script that is on page 2 (?) of the KitKat Explosion ROM 2.0 page.