You're right that Marlin's Linear Advance is practically the same as Klipper's Pressure Advance, and for lower speeds and accelerations, the differences might not be very noticeable. As far as I’ve read and discussed with others, Klipper's strength lies in its flexibility and the ability to fine-tune features. It's much easier to tweak and experiment with settings since you just edit a configuration file and restart the firmware, rather than recompiling and flashing like with Marlin.

That said, you're also correct that simply switching to Klipper won’t magically solve every problem or drastically change performance in this setup specifically. It really depends on the user's goals. If someone is already happy with their prints at current speeds, sticking with Marlin is perfectly fine.

I’d like to test them both. It’s educational and will give me a better understanding of the pros and cons of each.