I have Shure SE215 & 535LTD and Westone 4 & UM3X and I use the large triple flange tips (with the smallest flange removed). For me they are the best sounding tips with those IEMs and they fit my right ear very well. My left ear canal is just a smidge larger and the tip will only stay sealed if I don't move or open my mouth. Has anybody ever seen a small bore, long stem, triple flange tip in an extra-large size?
On many larger bore IEMs, I use Sony Hybrids and size L work for me most of the time with failry deep insertion. The Sony EX600 and EX1000 came with size LL hybrids and I use those with very good results on the EX1000 and XBA-4. The problem with the LL hybrids is that I can't find size LL replacements except as Sony spare parts for $17 each, which seems a bet excessive. Anyone have any ideas about sourcing size LL hybrids or an clone equivalent?