Doors and Windows - New Windows or Not? HELP!

We are having a few windows replaced due to hail damage. My wife is thinking about replacing all of the windows now..... However, I'm not so sure.

We have 10 year old, double pane contractor grade vinyl windows. They look and work fine.

The new windows are also vinyl, double hung and have welded seams, low E and Argon (but the old windows may have low E and Argon too, I'm not sure because they are 10 years old).

Anyway, is it worth the cost of replacing these? I'm mean, what's the life expectancy of builder grade vinyl windows anyway? Are these new windows that much better to justify the cost?

Buy the way, here's are the windows we're look at:
http://www.alside.com/windows/excalibu.htm

Thanks - opinions are appreciated!

If the frames of your 10 year old windows are fine, then why go to the expense of replacing them?

If you are in a very cold climate (weeks on end below freezing), then argon is probably worth having. Low E is certainly a must.

Would be much cheaper to simply replace the IG units of your original windows (the ones not damaged by hail) than to replace the entire window.

To recover your initial outlay of cash in a reasonable time the old windows have to be in sorry shape.
You would get a better return on a savings account than replacing your windows since your existing ones are in good shape :)