I had the same expectations, and unfortunately the same experience, they also offered me the first strike policy on 1 of 3 of my 6500ex inverters, the other two on my dime. Also ordered and paid for a special comunication cable gor my batteries, they sent the same cable 4x times, a 9 pin once, but not the cable they had listed, and refused to send correct one. I also had a display on my #2 Ex-6500 that had a bad micro usb port, reported with in 30 days of receiving, sent pic if M# S# of box, and display, they needed pic from unit side, had duct in way impossible to get pic, no replacement, rj45 worked so that's what was talking to the Solar assistant.
I DO NOT WISH TO GIVE SIGNATURE SOLAR ONE PENNEY OF MY MONEY. So I purchased a Sol-Ark 15k, been less than 2 months 2.6MW generated, whole house running on solar and battery, with grid back up, (wife /daughter want to run elecric drier @20:00) no problem unit pulls a little from the grid, garage does not sound like a airport mid day.
PLEASE FOR THE LOVE OF SOLAR, DONT PURCHASE FROM SIGNATURE SOLAR, as a Newby I was also very interested in an American based supplier, but it's mostly made in China, so find a good company to deal with!