I think the P500 is actually an optimiser, rather than a micro-inverter. It finds the MPP of each panel independently, within a string. Microinverters, such as from Enphase, also find the MPP for each panel, but operate on individual panels, not panels as part of a string, and avoid high voltage DC cable runs on the roof.
I think they are best suited to arrays with shading issues, and will help a bit, but shaded (even partially) panels are best avoided if possible, because they wont produce much output. Optimisers mean that one shaded panel doesn't wipe out the whole string's output.
Loomberah weather and astronomy including live solar radiation intensity and UV + Gunagulla aquaponics, organic eggs and cherries