Depends on where you live and what you care about. I sold a house full of windows for an expensive house in Stamford, CT, and expensive suburb of NYC (not the most expensive, but this house is worth around $1.5 million) and the homeowner insisted on GBG because of how often she washed the windows. She didn't care that the look was "architecturally incorrect". I tried to upgrade 3 times. The next house she built after a fire destroyed the house next door that she also owned, she used GBG again. I didn't sell any other GBG projects in Fairfield county over a 13 year career.

I moved to the DFW metroplex nearly 2 years ago and I've seen multi-million dollar homes with VINYL windows and GBG. Texans don't seem to care about their windows the same way people in the northeast do. Partly due to climate, they have used aluminum windows for many years. Not aluminum clad, just aluminum. Also the architectural styles prevalent here aren't as window focused. This is a casement window market while the northeast tens to favor double hung windows. Cost adds to the lower "grade" window tradition as does the other features they spend money on (even many tract homes have in ground sprinklers due to the severe summer heat).

So, yes, you can use GBG on windows in high end homes but make sure you aren't lowering the resale value of the home more than the savings realized or making it slower to sell.