They will be higher priced than vinyl. Are you settled on Milgard? Quote, quote, quote, quote, then ask for a re-quote.
Great choice on casement and awning, I can see you have done a great job with your research so far.
Do you have mostly singles, or do you also have assemblies? Any SDL's or casings? Have you settled on which glass coatings you will need? Dual pane with argon? What are the code requirements in your area?