I like the option of hanging these by hooks (which are included) or by a tension rod. My room  gets warm and these actually help to keep it slightly cooler making it more comfortable to sleep. I would highly recommend these, and I was glad I read the previous reviews which stated to purchase more than 1 to use for a slightly wider window. 

Pros: Seems very durable, works at keeping heat out, definitely blocks the light
Cons: Maybe some other colors to match curtains being used