I have a 530 as Box #1 and a 430 as Box #2, with a KNS 550 moving map in the middle.
I don't find either Garmin user intuitive although I have no major problems now I'm self trained in their use. My big gripe at the moment is the convoluted way they "auto" alter the display backlight settings (screen brightness) for night flying. These are coupled in to the main instrument panel lights and should gradually self adjust as it gets darker. They do change, but not to an acceptable level. I've had them go so bright in the default "AUTO" that it's impossible to see past them and so dim that the screen disappears altogether, most disconcerting. Every time I night fly I find myself having to go into the aux pages to manually adjust the brightness, which isn't straightforward, especially if you need to change it in a hurry, and it defaults back to the "AUTO" setting on every stop/start. Why they didn't just put a simple rotary brightness control on them like on the KNS I'll never know.
I've never carried a hand-held GPS though.