Spent a few days outside this week but the sky was a bit cloudy. I only got about 50 watts from the panel, but it's clear that it could do better with clear summer skies. The build quality seems to be good. no obvious problems. It looks heavy and hard. It comes with lots of adapters which is great as I have several different charging adapters with several different input ports. I'm just not sure about the price. There are other 100 watt panels that cost less. This one costs about the same as the well-known brands.