Speaking from extensive experience in maintenance of windows, both new home installs and retrofits: There are two major brands I have found superior for several reasons including longevity and repair as well as thermal efficiency and those are Pella and Anderson.
Both have their advantages and seem to shift back and forth over the years in my view as to which is best, but currently (at the time I finally retired) I give the fiberglass framed Anderson the #1 and the Pella the #2, rated on ease of maintenance with both neck to neck in quality.
They're no where near the cheapest, but not the most expensive either. If you're planning to stay in the house long they will save the cost of early failure and another replacement, if you're planning on selling soon you might look at some cheaper brands.
Pay extra if you have to, but get thermal panes (insulated glazing, about all that is made nowadays) that are inert gas filled for both thermal properties and longevity before they eventually fail and fog over inside. I don't know why this but I have observed it this way over long periods of time.
Whatever you do, get highly experienced installation, the vast number of problems I have seen over the past 40 or so years are the result of being poorly installed. Even the best will give trouble if not installed perfectly.