I wear a 3/2mm O'Neill Short John when it starts to get cool...it's a Houdini model which I've got used to getting in/out of..
And O'Neill 3/2mm Steamer when it gets colder here (water temp <18) which a radiator rashie under it and never feel the cold....back zip.
Give me a back zip anytime, those over the melon suits are a pain to get out of especially if you have a dodgy shoulder.

Also I wash/rinse in clean water (no polish) after every use and the Steamer is still ok and 7 years old