I highly recommend EcoView Windows and Doors of Raleigh-Durham for replacing old windows. My experiences with them were very positive when I recently replaced all of my old wood frame windows with vinyl double-hung windows. EcoView's quote was by far the most reasonable, and the sales process was easy and low-key, no long in-home demos or pressure to buy. The windows they offer are all from Simonton, and I'm pleased with the quality. The whole process from final sale to installation was quick, too. It took just a little over a month, and the installation itself required a little less than a full day. Their crew was on-time, courteous, efficient, and did a wonderful job. The owner came to my home twice during installation to make sure that everything went smoothly and that all of my questions were answered. Don't hesitate to give them your business!