While I've had some minor service issues with Signature Solar, and others have had varying degrees of challenges. I would encourage you not to get too hung up on the little details. They're a business trying to satisfy customers, they don't always get it right and they never will, however, they don't stop trying to make things great for their customers.
Signature Solar takes a lot of bruises in this forum, not because they're the worst, but because they're popular, they have good deals, and for the most part, they have the items and prices that solar consumers want.
To be clear I'm not defending Signature Solar, I'm simply saying at the end of the day, companies are made up of people, and it's a good idea to take a step back at times and remember kind and friendly behavior will always serve everyone better.