Good showerhead for low-water pressure

In 2015 I installed this Delta Water-Amplifying showerhead ($18) in a shower that has low pressure. It really does deliver a nice spray with large droplets. It's got a little knob that lets you switch between 2.5 and 1.85 GPM, but I had a hard time telling the difference. Installation is simple. Here's a good video that shows how to change a showerhead: https://youtu.be/fiv4Zq9v4co