I personally like 100% vinyl, for aethetics & ease of maintenance. It's a rare house with wooden windows or wood clad in rainy New England that the wood on the inside windows is without some type of water damage or stains. I like vinyl all white windows inside & out and white trim, always looks like the day you got it. Vinyl expands but that's engineered into the windows, the seals in vinyl windows have the same 20 year warranty against failing as those in wood clad. But, more importantly the Harvey all vinyl windows I have have a lifetime warranty, wood clad from Harvey, Marvin & Andersen only come with 10 year warranties so wood doesn't hold up as well. If you like the look of wood, that might be a good reason to choose it.
Which should you get? My father's been a carpenter for 40 years, in his career he felt Harvey windows were a step above the others, the only brand he's never had to do a repair job on, and only brand he's not heard a complaint about. He put them in his house, my house, my brothers house. But they only sell to contractors who have a construction account with them (not home owners) so that may not be possible for you to get Harvey. I just installed 6 retrofit windows last month, 3 were new construction and 3 were replacements. New construction should be avoided if possible in a retrofit as they require you remove the entire window and its built in frame, and all trim, in some cases that includes some of the vinyl outside and part of the wall on the interior. The only time one would get new construction on a retrofit is if you're making the window larger or your current show signs they've leaked or damaged the framing around them (bubbling & peeling paint under the window, water stains, rotted window, or carpenter ants around the window) all of which require you at least investigate and possibly repair/replace the framing around the window. In my case the reason I went with 3 new construction was that 2 windows were rotted and the paint below them pealing (leaks) the other carpenter ants were entering/exiting a hole in it (on the outside). I had to get to the framing around the problem windows to inspect so that meant new construction windows in those cases. Replacement windows you normally just have to remove some trim on the inside of the windows, then pull out the nails holding the aluminum chases, pull the two glass out and the chase will come with it and watch out for flying springs! After putting in the new you put the trim back on and touch it up. But, I didn't come across any instructions on how to cap the replacements with aluminum. Covering the trim with aluminum should be done where you live (rainy New England), with an aluminum bender, and knowledge of how to weatherize them properly so the task may be best left to the pro's. In particular after removing the old window you need to put in the aluminum that protects the sill before putting in the new window.
Here's some tips:
If you don't specify the window may come with half screens, I don't recommend half screens. When pushed up they don't seal properly and bugs sneak around them. If there's a chance of rain I like to open the my windows on the top 1", can't do that with half screens. If you want to turn on a house fan, only being able to open the bottom the breeze comes in the back of your neck drives me crazy. So, you may want to specify full screens.
You should mix & match the windows. The south windows should have as high an SHGC rating as possible (as long as the south side of your house gets sunlight). That's the % of free heat energy from sunlight the window lets into your house, higher is better. You can reduce your heating load by doing such, some people can heat their entire house through spring & fall just from getting windows with a high SHGC for the south ones and then the windows with a low U-Value for the other sides. As long as from the same company & style you won't be able to tell the difference between them. Unfortunately the windows with the most SHGC have the least insulating value and need to be covered at night (curtains, blinds, etc) else you can lose all or even more than you gained. Also in summer you want the blinds/curtains closed to avoid the free heat from the sun. Some people have overhangs that let the sunlight in during winter, but when the sun gets higher during the summer it blocks the sunlight from entering.
The grids you choose will make a big impact on how your house looks. If going for colonial you usually get 6 grids on top and 6 on the bottom, or 8 over 8 depending on the size of your current windows. If going for the cottage look you should get 6 or 8 on top, and 1 on the bottom (basically grids on top, no grids on bottom) which always makes your windows look like they're open & cheery both from the inside and out even when they're closed. Those interested in the most solar gain, will get 1 over 1 (no grids) as the grids inside will block some of the free energy from the sunlight.
Key features IMHO is that you can flip them down for cleaning, if you get the grids make sure they're inside the window panes, and I like removeable screens for the south windows in particular as they can block up to 50% of the suns free energy. I like to take them out on my South windows during winter and find being able to do that from the inside is nice.
Good luck
