More or less true. The cheaper stuff is usally made primarily out of roofing materials, and will melt, losing almost all of it's effectiveness in higher temperatures, as well as being less effective to begin with, so if you live in an area where it can get fairly hot, you almost get less than what you pay for. however i understand budgets and why people would go with the less expensive materials. However, It's much more effective to save up for the more expensive products, weather it's Second Skin, Dynamat, or any of the other higher quality companies, and just do the car small sections at a time. you want to start with the doors, then the floors, then trunk, and finaly roof. those areas tend to be most problematic in that order. if you purchase a cheaper product, do not apply it to the roof, as it will more than likely fall on your head at some point, which will be smelly, messy, and if it happens while you're driving, hazardous to your health.
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