I don't think you can say you overpaid, any profit (if any) made by the company should be irrelevant, you are happy with your installation, its doing what you were told it will do and you understand what you brought. You got a good deal on a good tariff, it looks good on the roof (which is very important). and is performing well.
Its the people who don't have all the above who i believe have overpaid regardless of price.
Its the people who don't have all the above who i believe have overpaid regardless of price.