I assume you are talking about these:
http://www.radiator.net/Item.aspx?CID=2&PID=5I think they work ok. I have become a fan of Radiator wetsuits. They are cheap but effective.
I used to wear a 4/3 Rip Curl Fireskin. Last winter I wore my Radiator 3/2 with the rashie all winter. So yes, I think they work.
The only criticism of the Radiator wetsuits is the zip and closure system is a bit basic. Rip Curl zips are much more resistant to flush through.