I have heard many good things about Anlin windows. I decided to get a quote and shop around as well. They have a very high energy efficiency rate and work with the engery tax credit. After they were installed, we wanted to see if they were as good as we were told. They seem to hold the weather outside and do not have any problems so far. I have had them for about a year now and they still look great and work well. They are more expensive than other windows, but their energy efficiency is much better than other windows as well. Just like other companies, they have a lifetime warranty, of course as long as they are in business and you are the owner of the home. These windows replaced our old aluminum windows which you could actually feel cool/warm air coming thru and it was just like having no windows at all. These windows have done a good job of keeping the temperature constant compared to outside and they are certainly worth the money.