Solar b/u batty for iphone

[arcproducts]

Has anyone used a product like this or something similar ?????

Just curious how they perform

from what i have read, it seems it will only charge your iphone back about 40-50% which if fine, as long as you know that. since the iphones discharge so quickly when in use (ipod, watching videos, music etc) while you travel, they show a picture of using the solar charger in the airplane window.

basically just trying to figure the difference between hype and reality before i go spend my hard earned money.