Neoprenes are fine in winter, but this time of year you will SWEAT ! I bought some Snobee Neoprene Chesties and can't fault them for quality, but they are just soooooooo hot ! Seriously, at this time of year, you will need shorts on inside them !
So considering the above, if you can afford them, buy a decent set of breathables. In winter they will serve as overtrousers if you like and keep you dry in all conditions, not just wading !
I believe a few on here have spoken about the Bison brand, which you can pick up on E-Bay quite reasonably !
My friend has the Diawa Neoprenes and they seem fine, the sweating problem aside !