No real maintenance for the interior besides keeping it clean.

I beg to differ. You will need to stay on top of wiping off any moisture on a daily basis, and they will need refinishing every so often as well. The people that don't maintain the interior are those that replace their wood windows after 10 years because they rot out. You can probably figure on some tlc being needed on the interior finish every 3 to 5 yrs or so. If you have never refinished a window before, it can be VERY tedious.

Karate guy
Why would you need to refinish the interior every couple of years?

If there is humidity in the house, moisture can/ will form on the glass and the interior wood frame. This is a problem as it can eventually lead to rot. Every other year or so requires touch up on the interior ensuring that moisture isnt absorbed. Most home owners accept this minor inconvenience but still neglect to engage in the proper maintenance, this is why a high quality vinyl interior , cellular composite, or fiberglass interior is recommended.
Ive seen many wood interiors rot, warp, or dry out beyond repair. Unless you remain vigilant , you are going to have a problem.
In fact i just replaced 9 Andersen Woodwrite windows that were only 6 years old.

This post was edited by mmarse1 on Sun, Jun 16, 13 at 13:03

Didn't drive down the details that far but Karateguy is correct that if the wood window gets wet, you are going to have issues.

If he is located in the desert or somewhere with a lower RH, that will not be an issue.

If the windows are sweating, the RH is too high in the home anyway.

Depending on your climate area I suppose interior maintenance could be an issue at some point but generally speaking it's not something to be greatly concerned about. Modern wood windows are insulated properly and if you keep your home's interior climate relatively normal it should be decades before you'd have to consider repainting/staining.

If the humidity in your home is so bad you are afraid your windows will rot from the inside, take that into consideration for the material that everything in your home is made out of...

Fenestration Taylor, the dozens of 10 to 20 year old wood windows that my company replaces on a weekly basis due to rot would say otherwise.
1) today's new homes are built very tight, however builder rarely grasp the concept that moisture + no means of escape = problems, especially for windows made of organic materials.
2) regardless of how efficient a window is, it will still be the coldest surface in a home, and therefore the first surface for condensation to form. This is compounded by the fact that wood windows are generally leakier in terms of AI rates, AND many homeowners cover them up with thermal blinds and shades in the name of energy efficiency only to open them up one day to find a soft black mess on their sash .
3) wood windows quite simply do not last 50+ years like they used to because of the wood itself. Genetically modified, fast growth pine cannot hold a candle ( no matter how many chemicals they add) to the stuff that they used 100 yrs ago. It is porous and hungry for moisture, so it is really a fight if you want it to last.

Ultimately, I will agree that the windows should not be held responsible for high moisture content in a home or a homeowners habits as they pertain to window treatment operation and attentiveness, but unfortunately these are legitimate issues that arise with a high degree of frequency. Our energy audits often include recommendation of a constantly running exhaust fan or hrv system, however tightly sealed, properly vented homes remain in the minority.

All that said, I believe that wood windows are a very valid choice, with the caveat the the homeowner have the right expectations. I would agree with karateman, mmarsel, and windows o Washington in that regard.