Simonton is definitely typically considerably better than Jeldwen. I would visit a real lumberyard. They should be able to show you a vinyl basement unit, even if the size is not correct at least you will have an idea what it looks like. You also may check with a larger mason supply as near me some furnish the units to the masons.

millworkman -- I'm about at my wits end and frustrated with the crappy windows available to me in Vermont. No companies within 75 miles of me carry any "premium" vinyl windows -- options are Pella, Harvey, Farley, JeldWen, American Craftsman, etc.. I'm going to triple-check that Anderson 400s can't be customized to our size. Assuming that fails, we are stuck with Simonten and Kaskel. Any thoughts on those two?

Simonton isn't the greatest, but it is a solid performer. You should be satisfied with that window if its installed properly.

update: We've ruled out Kas-Kel and are now deciding between Simonten ProFinish Brickmould 600 double gliders (0.3 U-factor; 0.28 SHGC; 0.53 VT) and Paradigm 8300 NC double gliders (0.28 U-factor; 0.28 SHGC; 0.52 VT), both are low E, argon filled. Their prices are comparable. As above, we are buying sight-unseen (grrr!!). We have only managed to find/see double-hung for the Paradigm and a lower-end Simonten (not Brickmould). Of these, Paradigm had cleaner welds and smoother operation, but again, we didn't have a direct comparison for our window type nor even the window series that we are actually contemplating. I would appreciate any thoughts on our comparison or additional questions we should be asking about these two options!