Windproofs keep the wind at bay and usually some rain, especially when combined with a fleece or woollen mid layer.
Paramo fleece moves a massive amount of sweat away from your body and is great in rain when combined with a Paramo windproof.
Hard shell or laminate waterproofs keep a lot of rain at bay and let some sweat out.
Paramo waterproofs move sweat away from the body best and are the most comfortable option in heavy weather, you will need to wear less underneath than with a conventional waterproof and you will find that you take them on and off much less than a laminate shell. Paramo is the waterproof of choice for all our staff (including 3 mountain leaders) in heavy weather.
Lightweight waterproofs still keep the rain out and are great to keep in your bag in case of rain.