Before anybody buys these foam tips from lostearbuds, you ought to know that their real size is at least one size smaller than their nominal (stated) size. So, if medium stock tips have always been too small for you, forget about trying lostearbuds' tips. Even the large ones will not be big enough for your ears. See here Alberto's and other reviews on them from Amazon.com:
Those issues are discussed in this thread also. You can search for "lostearbuds" and you will find. "putente" is the person who introduced everyone else to those tips, in this thread.