you want to wear a dry suit in NEW SOUTH WALES? are you
mad?

I used to use a dry suit in winter in the uk. There's quite a few benefits and unfortunately a lot of drawbacks really.
Benefits:
- Body dragging is somewhat more efficient, particularly upwind
- you get some extra flotation from the suit when in the water
- nice and warm. the warmth gets controlled by layers. I.e. some days I would wear just a tshirt and light jumper and usually shorts +- leggings or occasionally just the trousers I was wearing before. Other days I would wear a longsleeve shirt followed by a tshirt followed by a thick jumper. Ideally nylon or wool but you can mix some cotton in too really...
- warm feet
- When you are done with your session you can take the suit off and drive home. Takes like 30 seconds.
Drawbacks:
- first and foremost the suit traps air. You can release this a bit by trying to curl up and letting some air out via the seals but a significant amount still stays. This means that this air is gonna move in the suit. when you are in the water it will move to the top of the suit.
You will now become incredibly immobile. It is very hard to lift your feet out of the water and put them into footstraps because you a) need to invest quite a significant effort into lifting your legs and b) it becomes really tricky to reach forward and even pull the board towards you
You basically are like a beetle on its back and just very immobile.
Also, the moment will come where you will fall and crash into the water with the kite yanking you and your suit will really hamper your mobility while submerged.
I think this is less of an issue in more expensive suits which have a vent valve
- you need to wear boots/wetsuit shoes (usually 2 sizes larger than you normally would take). They don't fit in all footstraps.
- If you spend too much time swimming or standing in deep water the waterpressure on your feet can become quite painful
- i don't take the inability to pee as a negative. If you are out of the water it does not take long to undo the zipper and I have certainly never peed in my wetsuit either.
- dry suits need maintainance (!) You have to lubricate/wax/grease the zipper before every session and the suit will start to leak - often at the seams. That can be fixed but the tailor needs to occasionally make the suit a bit tighter when doing so which can cause problems.
Overall I do not really think it is worth it. For most kiters the cold gets more to the hands, feet and face anyways.
In England a lot of people wear 3mm wetsuits from May onwards if it is sunny - in 11-12`C water. With that in mind you should easy be able to wear 2mm or 3mm all year round in NSW...