i bought new vinyl windows for my home 4 years ago.. paid quite a bit for them... they were sold as having the potential to save me as much as 33% on my electricity bill.. to date, i havent seen a 33% or anything near that in my electricity bill, let alone gas bill for heating... i work in sales, so what people say to me in a sales process is important... as a former sales manager, i was always watching that my sales reps never oversold the product and made claims that could never be met, thus causing sales credits and bad pr... the sales person on these windows used a heat lamp and one of the whirly birds in a glass to show me how heat didnt transfer through the windows he was pitching to me... when the people came to put in my windows (a 3rd party installer) he told me i might be eligible for a tax credit if the windows met the required standards.. they didnt meet them though... the original sales person never mentioned anything about a possible tax credit in the sales process although he did his darndest to sell me on how they would help in my heating and cooling cost... to date, ive always wondered if the windows he showed me in the sales process and the ones that were installed were not the same level of efficiency...