I'm writing this about a year after the installation so that I had some good perspective. After a fair amount of research, I knew I liked the product that Arrow 2000 carried (Armor series). I obtained quotes from 3 GTA carriers of this product. Arrow had the best price, and I also liked their salesperson, Rob, the best. I also liked that it was a family business and Rob (son of owner) had been in the business all of his life.
The average cost per window might seem high but I had two huge windows (one arched) that were in the $2500 range each, and as I say, Arrow 2000's overall quote was best. As far as installation goes, the crew was nice and I felt they were sufficiently efficient and clean. I wouldn't call their execution flawless. I had one window that came with the hardware on the wrong side, and one with the wrong piece of glass (miscommunication). Also, I live in a Victorian and they weren't prepared for the amount of dust and junk that fell out of the walls (I went brick-to-brick). They also didn't adequately warn me of this or I would've covered and/or put a lot of stuff away. However, in every case, Rob made things right. Particularly impressive was that he offered up his office cleaning staff to come in on the weekend and clean up the copious amounts of dust and debris on my main floor, which included washing the floors. All on his dime.
So while not flawless, everything worked out, and I thought the after-service was really good. He cared. And for that reason, I will use them again and I would definitely recommend them to others.
(Note: I think people mark too easily on this site. I personally think 9/10 is a great rating. To me 10/10 would be flawless.)