I purchased American Craftsman Windows (casement)when I build my new home about eight years ago. I have experienced no problems with condensation, or other adverse conditions resulting from poor window construction. The only experience I have with a problem concerning these windows is when my teenage son used brute force to open a latch while the outside weather conditions were extremely cold. As a result he broke the latch. Here's the test of a company's claims. I contacted Silver Line Windows the manufacturer of American Craftsman. Explained the parts I needed even thought I no longer had the "I.D. number". The person was polite and knowledgable, and told me the parts would be shipped immediately. A few days later I recieved the correct parts "no charge". I can't remember the last itme I had such an easy time with a manufacturer.