All on the same path... Oh wait. I understand you logic, obviously ambient temp increases after each heat exchanger and therefore delta T drops and you become more susceptible to overheating; and lets not forget cost like you mentioned! But a track car with no ac and oil/brake coolers on the sides, it makes sense to have front mount intercoolers because the air flow is much greater there than the small openings on the sides. Until someone throws some thermocouples in there and measures ambient air changes with both setups with similar conditions, all of these opinions are just that....opinions.