I did another forum search, and this was what i found regarding splash screens.
http://forum.ppcgeeks.com/showthread...+splash+screen
So, aside from this they would be unable to tell that it is Juicy rom? Isn't there a Juicy Rom label somewhere or wouldn't certain system / os numbers be different? And from this i am also assuming that adding programs etc doesn't void warranty, only unlocking and flashing roms.