Fleetwood

http://www.fleetwoodusa.com/

Milgard and Fleetwood are both good to look at. Another is Blomberg. It is a smallish family run company near Sacramento. No web site. Call them and they will send a nice packet. Beautiful product.

Cost-wise, it goes Milgard (lowest) - Fleetwood (mid) - Blomberg (highest). Blomberg is maybe 2x Milgard.

Both Milgard and Fleetwood offer 'thermally broken' frames. But strangely, the Milgards are not available in California... So if that is an issue for you, Fleetwood may be a better choice.

We went through this last spring. A nice thing about aluminum frames is that they are thin by comparison to other styles. So they look better in modern/contemporary designs. This is probably why your architect is steering you towards them. Ours did too.

In the end we chose Milgard, and are very happy with them. Got the dark bronze frames - which look very cool. Also got the Solar Max glass. We have a mix of casements, and sliders. Also two sliding doors - with fixed windows above them. (Vaulted ceilings.)

Excellent info. Thanks!

I've been doing the same research for the last month. Here's what i found:

International window Corp (IWC)
MI Windows (a.k.a. BetterBuilt)
Superior Windows
Milgard Aluminum
Fleetwood USA
Bonelli (in South San Francisco)
Gerkin (midwest)
Torrance Aluminum (Southern Cal)
Western Window Systems (AZ)
Lanai Windows SoCal
World West Inc.
Sunview Doors (Toronto)
Heritage Window Systems
Blomberg (Sacramento)
Oceanside Aluminum (San Diego)
All Weather Architectural (Vacaville)
Metal Window Corp (Southern Cal)
LaCantina (soCal)
VistaWall (commercial)
Arcadia (commercial & residential)
DeSCo (midwest)
All Weather (Texas)
Peerless (midwest)
NewTec Windows (IL)
Boyd (midwest)
Thermal Windows (OK)
StoreFrontDoors.net/Kawneer (commercial)
and there's another company in SoCal who makes beautiful windows and lift and slide doors...I can't recall their name...starts with a W i think...very expensive