You are thinking of Silverline - not Simonton. Simonton makes a superior grade vinyl window.
Silverline became the largest vinyl window manufacturer in the world by means of the American Craftsman (Home Depot) window, selling the Silverline name thru other channels, and also the Stanley brand name window thru yet other forms of distribution. They are all the same window.
They definately have a rep for occassional poor quality due to high speed manufacturing and no possible way to verify quality before the finish product is packaged. If you have ever seen this type of manufacturing you would know what i mean.
It is what it is. If you want quality, i would look elsewhere (Yes i am a window guy)& (no, i'm not going to try to pitch you "my" brand) there are many brands out there. On the other hand, if that's what you want to pay it's still pretty amazing you can buy windows for that kind of money compared to what has happened with the price of so many other products/materials recently.
Oh, yes Anderson did buy Silverline a few years ago, but the product remains unchanged and of course is still made in the same plants. It is ownership only - they aren't made side by side with Anderson Windows.