You're going to get a bunch of different answers to this question. There's alot of variables depending on the type of wick, the
juice used, the type coils used, etc. my rebuilt Vivi nova cotton roll wicks last a week or slightly more, but I usually just switch out a new coil on the weekends. Cotton has great flavor and wicks real good even with my VG juices. They are
juice hoggers though and use up alot because they wick so good.
edit...oops. Just realized you are asking about rebuildables. I make cotton wicks in my Igo-l's also and it's about the same, about a week, if I'm using it exclusively.