I'm no mechanic or automotive engineer, but I spent the $400 and installed the K&N NextGen 50-1578 COI on my 2021 RAM 1500 5.7L Laramie 4x4 and am thoroughly impressed with it. It was a simple install, even for an old man. The unit came with dyno performance charts for this specific engine, showing increases of ~20 HP and ~20 ft/lb. torque with the K&N over the OEM air filter box. It sure seems like it when I step on the gas. It sounds throatier, definitely louder under heavy acceleration, the tires will burn rubber quicker, and the truck goes faster, faster. But it's not noticeably noisier during normal driving conditions, just a little deeper engine sound. I can't corroborate the actual numbers, but I'll attest to the initial benefit of the upgrade. Long term usage is still out, but I love it so far. At the rate I drive (<10,000 miles/year), I'll probably never even have to clean the filter before trading it in.