Escape bivvy looks nice, they say they have dealt with the condensation issue. I have used the emergency and thermal bivvy in near freezing temperatures, just to see, and they do help a lot, but you always have the moisture.

the Space Blanket is not to be confused with the small foil survival blankets. It is heavier and a bit bulky, but it is durable and has grommets so you can use it as a shelter. It will not fit in your pocket. It is useful as a cover for a blanket of sleeping bag, it is waterproof, windproof and increases heat retention. I have slept in temperatures around 25 degrees Fahrenheit with a poncho liner, wool blanket and Space Blanket and was was surprisingly warm. I usually still carry a Space Blanket in my backpack.