When a/c is on windshield is fogging up when driving in slow traffic. When on highway, fog disipates. Have tried both normal & recirculate, no difference. Anyone have this problem, or any idea's. Or should I just bring back to dealer?

if so, it will fog up more easily on cold days, if its not on econ, and it fogs up significantly and doesnt recitify quickly, then there maybe an issue with the compressor.
With recirculate, eventually it will start to fog up, but only after quite a while.
Anyway, if its on econ, then thats the reason, if not, check it out at dealer.

need to push a lot of air to cover the whole windshield. Hence, in the summer they tend to 'overcool' the center and cause condensation at lower speeds.

the air flow spread out, its not just focused at one spot, clearly this is a problem with the compressor, its not drying the air for whatever reason.