Product review (5 stars): Works Well - Only InSinkErator Stopper That You Can Leave In Place
The only sink stopper I have found which can be opened (for draining) but left in place.  All the others need to be removed from the drain.  Polished nickel is fine but would have preferred that it be available in brushed chrome.  Doesn't seem to exist.  Functionally it works fine.  When open, it drains quickly; when closed ... no flow, no leakage.