Buying components for flexible design

James J., I believe in smaller dedicated systems myself. If you are just using the power gained for your own needs, why not have several, smaller, redundant systems operating instead of one, all purpose system. Then finding discontinued panels would not matter so much since each system would be specifically designed for a purpose and all panels could be purchased at that one time.
 Also, if one component fails in your combined system, then your complete system could be shut down. Smaller, simpler items for installation and operation may even cost less and last longer. Then component parts can be moved around if needed. Less complicated components may not be as fussy when it comes to adding mixed outputs.