We bought 13 windows that were the 4000 Series with Low E & Argon from Window World in Davenport IA on November 2008. We have had nothing but problems since. We spent $4735.94 on windows that were to save us money, not cost us more. Since day one we have had issues with condensation on the inside glass which has caused mold and the paint to peel away from the frame. We have contacted Window World too many times with this issue. They have replaced the windows 3 times now with the same shitty window. This was to correct the issue per the... read full review »