Aldo I have not got the GB580P jet, I can see the advantage of your idea. But for me it is also very important to switch from navigation to user page quickly, you don't want to press to many buttons while driving down hill with 60 km/h. Best would be to have at least one little screen in navigation where in a loop the most important values are displayed, like speed, hrm, cadence and high. maybe as little as the clock display mentioned in the GH625xt. I like a bit bigger more, but it would be a good start.