Transmission coolers

[04Xrider]

I picked up my 700r4 from a guy who has been building transmissions for a very long time, he was converting the electric speedo to cable drive, anyway, he asked me what I was using to cool the transmission, and I told him I bought a aluminum radiator with tranny cooler. He said I was way better off not using the radiator cooler and just add a aux cooler, the kinds that just mount in front of the radiator. He said the transmission would practicly last forever if I did that. He told me that the radiator coolers were just short of worthless, and that the aux cooler would cool much better, and also the engine would run a little cooler. I bought the radiator with a cooler, but I am going to take his advise, because one thing I know for sure, and that is, he knows a whole lot more about that stuff then I do. Anybody have any thoughts about this?