Of all my chalices stunner has longest sweepers. I'm under the impression that chalices will sting each other unless they are from the same genus (which because of the large number of them and the widespread use of common names versus scientific is very difficult to know). That being said I have a ton of chalice frags that are fairly close to each other with minimal issues. I do make a point to check them out regularly at night to see who has long sweepers.