Using the MIUI.us DefX version of MIUI. The developer and supporting cast seem to reside over at Rootzwiki. That build of MIUI seems to be leading the way in terms of Droid X ROMs IMO. The galnet version is also an option but I'm wary of it b/c it uses framework not yet released in any official Droid x ROM. Also the developer of that one seems to kinda trail the other build and just incorporate the fixes as they come out.
Lol, I just bricked my phone trying to flash this ROM.
Had to SBF back into stock Froyo, which I guess is for the better, because I saw a YouTube of a guy saying you have to be on stock Froyo rom or a CM rom such as CM7 or liquid. I was running Liberty, which the baseband wasn't compatible with miui.
Once my phone is done charging I shall root it and start the process over again ^_^