I say try it, I do use my own cooked roms, been using kalc's kitchen and works well. I am getting to the point of modifying some of the stuff now, but the basic kitchen is pretty easy, then convert cabs to oem's or exp's and your good to go. (theres a file I found somewhere that has a good program)
Heres a link to it
http://forum.ppcgeeks.com/showthread.php?t=76576