I did the same mistake of someone else, buying this item looking at the photo, which showed a bright/clear light, and not reading properly the title: "Recharge rear light".
Anyway, I needed both so I kept it and I am happy with it. It's particularly good if you own more than one bike and from time to time you need to use the other one, you don't need any kind of mount installed on both.
As a rear light it seems to be quite good, I cycle in city roads, but I *guess* as rear light it would be good on country roads as well.
I'm only worried about how long the rubber band will last, if I plug and unplug it everyday even during the winter.
It seems to be quite good, though.
Also the band has several holes, but I'm not sure how people are supposed to use any hole but the last one (larger) on a frame.
Still need to test the battery life, starting using it now as days get shorter.
Also not tried under rainy situations.