Greybeard---ive never been to Cozumel but went further south to Belize---I would suggest that whatever tippet that you take, that you shouldnt be satisfied that its new---test every spool and be satisfied that you dont have a bad spool like we did. There werent any fishing supplies in San Pedro and luckily we found a guy with a spool of 6# xt and used that all week. Take plenty of what you decide to bring , you may not be able to get it there.