I Bought a Clear Spindle Ioun Stone so I don't need to eat or drink, but my table mates(other players not gm) tell me it was a waste of money because my ring of sustenance does that. However the description only says it reduces sleep needed. Does it actually get rid of the need to eat and drink?
It's in the first part of the description, where it says it "provides the wearer with life-sustaining nourishment."
More to the point, it does so "continually" once you have worn the ring for at least 24 hours.