my vinyl windows are 12 or 13 years old, I have replaced 3 sealed units
2 of which take heavy abuse of 4 dogs jumping against. spent about 100
bucks on the sealed units, the manufacturer reynolds got out of window
business and the local dealer wouldnt return my calls. lifetime
warrantys dont necessarily last forever.

my windows havent had any troubles other than a couple minor
adjkustments, they have metal interior reinforcements.