IAT's with boost are an interesting thing, and as stated controlling them is 100% up to the efficiency of the core/cooler you are using.
On a non intercooled M45 Eaton setup on a J-body (Quad 4) I've seen the temps start out at 80 degrees on a 5 degree day and shoot up to a clean 140 degrees of IAT... that's insane! Meth can usually keep that down in the 80 degree range.
On my turbo setup I can keep the temps within 20 degrees over ambient, up to about 15 psi of boost. Then it starts creeping up (on the way to 21 psi) due to the efficiency of the cooler. To offset this I could install a CRYO2 kit or meth.
Heat compounds when boost is created, it's an unfortunate by product of kinetic energy... compression creates heat. @ 10-12 psi with a good cooler you should see 10-20 degrees over ambient. If you REALLY want to chill the air, a CYRY02 kit pre-aftercooler would bring your temps down well below ambient.
The beautiful thing about aftercoolers is there are plenty of ways to bring down the temps. On a straight manifold setup, you're at the mercy of a weak plate between the charger and manifold which really can't be anywhere near as efficient.