Buy Now, Pray Later! Pray they work that is. Apparently every panel is different and many are sub standard at manufacture.
Some companies test each panel but most won't bother as they take delivery of a bulk lot from the factory in China... the middle men and companies here in Aus will still sell the dud panels on knowing full well that they don't work or barely work at all.
Had a mate who bought some for his 4x4 camping set up from a big off road specialist and they didn't work at all- he paid cash and when he finally got the rigged out camper and off road trailer together, he'd lost the receipt for the panels. He had electricians look at the array... ended up taking them to the tip.
