My position re. ’most important’ is further upstream. Power, power supplies, power conditioners and the supplying cables, connectors etc.
Reaffirmed once again (this past weekend) by a different approach: with an on the grid vs. an off the grid demonstration. Quite something. Immediately and easily heard and distinguishable with performance/SQ improvements across the board. Grid vs. Solar panel > Battery > Inverter, etc.
A shout out to Richard Gray for the fantastic and illustrative demo.