Bought these for 7Hz Timeless IEMs and I don't know if it's the IEM shape, my ear shape or what, but these were very uncomfortable for me and made my ears ache quite quickly, cause the core is aluminum I think, which I didn't read and so it's quite stiff and hard (though it's the purpose of these). Also they none of the sizes fit too well.
I suspect that if they fit your ears better or your earphone piece is better fitting for such stiff ear tips they might really be wonderful. Unfortunately not for me.
I do love the Xelastec II and they are THE ONLY ear tips that suit me and my 7Hz Timeless well AND makes them sound great