Wut. The poll has nothing to do with the thread title...
To answer the question in the title, Fizik tape stays pretty clean on its own, with an occasional wipedown.
Fizik microtex FTW...and I never really thought about it before, but I really dont clean it all that often, so I guess it does stay clean on its own. When I wipe my bike down I use diluted 'greased lightning' so thats what Id clean the tape with...