I wore snorkels during my pool sessions. During my check-out sea dive, it gave me a freak out while doing the mask removal/clearing skills, the extra weight made it harder for me to return the mask on. Also, for some reasons, whenever I reached out for the BCD inflator/deplator button, it's always the snorkel mouthpiece I touched. Additional freak out/panic moments. I ditched wearing it the second dive during check-out and felt better. If at all required, I wouldn't mind bringing one as long as it's attached somewhere else other than my head.