The years have proven that the two Solar systems Michael installed were a very good choice for me. I still keep fairly regular records of both systems performance my latest calculations show things are as good as new after nearly 8 years.. Importantly the economics have been proven with the 50 cents/Kwh rebate. Since September 2009 we have not paid an electricity bill and last month I withdrew a $2,000 credit from Origin. The foregone electricity bills average $1,300 per year. This all means the PV system plus the solar hot water plus the house insulation costs have all been recouped and the system is less than half-life.