To me, this is the intercooler to get:
Kia: Comp. Intercooler Kit Kia Stinger GT (US) Kia Stinger at wagner-tuning.com.
www.wagner-tuning.com
Goto 'DESCRIPTION', and look at the temperature graph - the charge is barely above ambient!
With this installed, and at full throttle, your engine will think it is sitting on the beach at the ocean, ...under an umbrella, ...a drink in hand, and a very cool persistent breeze blowing in from the water...
That is what an intercooler is supposed to do - and in this case, bigger is certainly better, and not an item where to try and 'save weight' due to thermal mass considerations. Thermal mass is GOOD - just like it is with brake rotors.