Hi, I was hoping that someone could give me some advice on some plumbing for a new shower I'm working on.

We're planning on having 2 (High-Efficiency) shower heads plus a rain maker shower head as well. Each shower head will be controlled by their own mixing valve, and off of one we'll have a diverter for the rain maker.

The supply to the house is 3/4 inch, and that's continued into the water heater and back out, so I do have 3/4 lines I can tap off of, but I was planning on using 1/2" pex for the entire shower. Am I going to have a flow issue with only using 1/2" or should I just do everything in 3/4"? Should I do 1/2" and do a pressure balance loop between the valves? Please advise