I have a Garmin 500 (no maps). I have my display settings so I can quickly scroll through the screens and have my basic ride data on the main page (screen 1): current speed, cadence, and HR. The other screens are only viewed occasionally: distance, ride time, elevation gain, max speed, average speed, and current time (clock). If you have too much stuff on each screen, the numbers can be small and hard to read at a glance.