40 PSI works very well.
Removing flow restricters on faucets (1.0 fixture units) would be pretty messy. Newer faucets have 2.0 GPM flow reducers, and I've seen 0.7 GPM reducers that do a nice job too.
At the old 5.0 GPM, that was a lot of water.
Outside faucets (2.5 fixture units) and inside washers (4.0 fixture units) have no flow reducers.

Terry Love

: FYI the flow restricters for faucets are regulated by law to an amount that is based upon an average incoming pressure of 80 PSI... Where you have 40 I would imagine you should remove the flow restrictors.

• Sizing water lines