I hope you're intending to use double glazing for thermal insulation and not sound insulation. (double glazing has no/minimal effect as sound insulation)
PVC frames have been used in Europe for quite some time now.
Alluminium is tried and proven but often doesn't look very good if used in a colonial type house.
Hardwood frames are good too but obviously require maintenance (painting)
Maybe ask these window companies that bag UPVC frames why they are no good.
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