I hope to replace my windows with vinyl replacement windows. I have similar quotes for Ellison 1300 and Simonton 5500 windows. Which window is better?

If you surf Simonton's website they offer a comparison of their products to others. Might be worth a few minutes of your time.

Both are good windows. Ellison has a 7/8" glass unit and Simonton has a 3/4" glass unit. My personal prefence for that reason is Ellison... they are similar. :)