We have 34 large custom windows we are replacing (no double hung - all slider or picture). Initially, we wanted Anderson but the quotes were ridiculously expensive, so that is out. We have quotes now from Preservation, Simonton and Northeast Building Products. I am getting one from Great Lakes. They are all within the same range. All installers are independent and reputable. We like the installer for NBP the best - he's been doing this a very long time and excellent reputation. Any thoughts on these companies? I keep seeing reviews and they say the products are good but not great.