I bought this along with the EMRG. The light on this one shined for over 24 hrs continuously right out of the box! Amazing! The bad news is that I can't get it to charge back up. I placed this model and the EMRG in the same window at the same time. EMRG charged in a few hours but this model sat in the window for 3 full days and never recharged. Drove around with it on my dashboard for a whole (sunny) day also no charge. Not even one dot on the power meter. Not sure if it's my device or just the wrong conditions for recharging. Assuming you can get your device to recharge I would recommend this device.