I have done tons of research before picking LongLife windows and I am glad that I made a right choice! They recently installed 14 replacement windows and 2 patio doors at my house. They are not the cheapest but their products are among the best you could get, solidly built and so smooth to operate. Paul and Kris were so easy to deal with, from the initial home visit to answering all my questions and concern. Bernard and Sean did the measurement and installation. Bernard's workmanship is second to none. His measurement was so accurate so that we maximized the size of the windows. He paid so much attention to detail (also a good sense of humour!) to make sure every single window and door were installed properly - and look great. He even repositioned all the safety bars and fixed the metal gate for me! My understanding is that the company does not use sub-contractors and all of their installers are employees. LongLife assigns enough time to each job so that they can do a good job.
If you are looking for new windows and want to have the best products and installation, go with LongLife. Highly recommended!