Depends. With my Vostok it wasn't really necessary since it doesn't have a date window but when I bought the Seiko SKX-007 I decided to get one because that watch has both the day and the date. Saves me the hassle of having to reset the day/date.
Finally figured out how to properly program this thing. Aside from the complicated memory bank types, I don't have enough good things to say about this radio. The audio quality of the speaker is excellent and it's nice to be able to put in full alpha tags instead of being limited to five or six characters to name a channel.