Depends who you ask

Truck coolers are only bad for the intercooler market. Intercoolers are seen as "boring stuff" to truckies, but to "fast and furious wannabes", they are a precious commodity.
Why is a truck intercooler 1/4 of the price of an HKS unit the same size? Because the wholesaler makes 100% "wanker tax" and then the retailer makes yet another 100% "wanker tax".
DON'T BELIEVE THE HYPE.
Both my brother and old man are using the same core from a big Volvo Truck Cooler. They both have S13 SR20DETs. They made their own intercoolers, and both are making over 150kW at the wheels with standard everything else. They both made an intercooler of the maximum size for their respective cars, and it's cost them <$300 each.
Goto nissansilvia.com and realise that the HKS equipped tossers are lucky to get even close to that with standard turbo/injectors/ECU.
If someone wants to argue that bar and plate does this or that at 400kW..then find me a car that has this much power and I'll reconsider. But for street applications, which 99% of cars fall into...a truck cooler works great.
Chris