i think i would have to go with only Beatles too, because they have such a varity of music, so it would not be like listening to the same thing over and over again, at least not to me. and anyways, im not really in to that many other bands, so i dont think it would be too much of a heartbreak to me.
and besides, you could just stop listening to music for a little while, if you were getting bored with them. its not like you have to listen to them constantly for your whole life!