Bingowings said:

Back To Reality worked for me not only as a solid comedy episode but also as a solid science fiction story (the best Red Dwarf episodes do both).

There is only one Holly who is sometimes male and sometimes female.

You might as well ask who is your favorite Talkie Toaster.

Yeah Back to Reality is a favourite. Also Gunmen of the Apocalypse which also works on both levels. And your right about Holly as a character, but I would tend to lean more to Norman Lovetts Holly ( just a personal preference) But there still remains question, the others will have to know!..does anybody want any toast?