I've got a mix of windows in my old farmhouse -- some drop-in vinyl replacements (Simonton), some original installations in a 1990s addition (Marvin wood/aluminum), some custom installations in an existing rough opening (Pella wood). Of the lot, Pella is the best. They offer wood, fiberglass and vinyl construction.

I was less sensitive to historical accuracy and installed casements where I could. They're far more weathertight than double-hung windows.