Yeh but this is why all these charts (btw no offence by this) mean nothing at all. There just useless in real world environments.

They give a expected idea but they dont take into account the following

1) Dead spots
2) Fin density
3) Tubs in the rads
4) Flow rates
5) if there copper, brass or ali
6) fan speeds
7) amount of metal used

i could go on forever but over all the chart means nothing esp when we getting a 3 x 120mm rad to perform close to a 4 x 120mm. Its theory that's all and a badly made 4 x 140mm rad can under perform a decent made 3 x 120mm rad and the same goes for some of these external rads as well.

e.g in theory these thermal fin rads sound good on paper but in reality they suck big time. All look at the size of them there HUGE .....