I had CDA put in 9 retrofit double pane windows and one kitchen sliding glass door to replace my 45+ year old aluminum ones. The price was much lower than I feared it would be. The job took about 7 hours to complete, including cleanup. I still had to vacuum afterwards, but I'm a bit picky. ;). The sliding door install involved much fiddling and adjusting, because the previous door just barely allowed the adjacent kitchen pantry doors to open, but they managed it with no problems.
I *love* my new windows! I can now actually see my view, instead of blocking it out with blinds all the time to cut down on the heat and glare. The windows slide and lock easily, and the screens are virtually invisible. I got a transferable lifetime warranty as well. I definitely plan to hire CDA again to replace the last couple of windows.