Hi Mike I had a big bar and plate intercooler like the one in the pictures 10 years ago. I had water temp issues (and was bloody heavy!) and have changed to a sizeable tube and fin core (which I assume what Pro Alloy is recommending).

I remember driving the car hard one night just after fitting the bar and plate type cooler and the inlet pipe too hot to touch but outlet pipe was cold with condensation on the outside!

Just couldn't live with the temp gauge rising in traffic on 30C degree days. Tried Redline water wetter with no effect. Maybe a different story in your autumn, winter or spring

Hope this helps mate