My stoma (Sybil) is an outtie, too. Due to weight loss prior to this surgery, my skin is not flat around my stoma, so the convexity is what works for me. I also use a skin cement (Osto-Bond) and have rarely had any leaks since. It's worth a try for you. You should be able to get a sample or two from your WOCN nurse, or even the company you order from. Good luck!
Ulcerative Pancolitis (dx'd 6/2002)
Colectomy w/ileostomy 6/2/09; i
ron infusions; Aranesp injection every week for anemia;
Remicade; Pentasa; 6-MP; Prednisone; Lialda; Asacol
various meds for other conditions