Best Bang For The Buck - Windows

In reading past post on this topic I have read opinions but anything I have read seems to be quite old and a lot could have changed over the last couple of years. If we need to replace all of our non landmarked brownstone windows, what is the best bang for the buck out there? I drove past a gorgeous house today that was under construction and saw the Crystal label on them. Marvins seem to be the most loved but certainly the most expensive. A lot of mixed reviews on Kolbe windows on Brownstoner- Not much talk of Anderson windows. I saw Cate purchased Champion windows and loves them…. If we are living in this home (not an investment property), what exactly should I be looking for in a window? Also- What is the overall price difference from lets say a champion to a Marvin?