Mark Michaud SELAUSAR
Contributor
As a real world rule of thumb.............mostly dry, always warm. I prefer a neoprene drysuit, but I don't dive really deep where that could be an issue due to the neo compressing. I have 2 Oneil 5mm neos. I installed P-valves in both, myself. Other than sweat, little water gets in. My first cave instructor (Pat Watson) stated it this way......"You can either be dry or warm, can't have both" That is mostly true. I have not flooded a suit since the mid 90's so a little water is no big deal. A bit in the wrist or neck is hardly an issue.