If you compare the size of the turbo cooler to the main rad, you can see just how little difference this would make.
The 82C stat is a con and not needed, people are always ignoring the basic facts about cooling and concentrating on just the water.
Fact is the OIL does as much cooling as the water, so any cooling to this will have a knock on effect, "high" temps of 90/93 do NOT kill head gaskets, it is for this reason I have bought some(air) oil coolers, with a stat sandwich plate.
I have been in 28C sat in traffic for 6-8 hours on occasion, I overhetaed but not the car.
I think imo if you have a alloy rad then all should be well.
I will be taking turbo water temps, before and after to see exactly what the situation is.
tabetha