Don't use my G string often ( [emoji33] that doesn't sound good...!!!). But I do use it enough for octaves etc.....so I need at least 4 strings.Come in Doude!! I used to only play 6ers. Take it from me, if you can't do it with 4 (I'm considering a 3 string) then something is wrong man!
The reason I use a fiver is the we do some songs in Eb Db etc....need the ability to easily get those notes in multiple octaves...