I must be really odd...after the first day of diving in Bonaire with my 3mm suit, I continued the remainder of the week in just a dive skin for protection against jelly stings only (fortunately I did that, because my dive buddy was wearing a shorty and came up in a big bunch of jellies!). I was comfortable the entire time...this was completing 3-4 dives/day (including one night dive per night).
I would recommend you take a 3 and a 5mm, so you have the option, if the 5mm is too warm...unless you would be comfortable renting a suit from the shops there.
