A faucet with an interface in terms of the two attributes you generally care about (pressure and temperature) is in theory much better for everyone than one in terms of two implementation-detail attributes (amount of hot/cold water flowing into the mixture).
Unfortunately many of the one-control faucets have terrible mechanical engineering under the interface, and as a result you often can’t adequately control either pressure or temperature, and the two aren’t actually separated orthogonally (i.e. as you move the control along one axis both attributes change, and to change just one attribute you must adjust the control along both axes)
Unfortunately many of the one-control faucets have terrible mechanical engineering under the interface, and as a result you often can’t adequately control either pressure or temperature, and the two aren’t actually separated orthogonally (i.e. as you move the control along one axis both attributes change, and to change just one attribute you must adjust the control along both axes)