Aluminum will conductively transmit a lot more heat in/cold out than aluminum clad wood ever will. Plus, an aluminum window always looks like... a cheap aluminum window. Go with the wood.

I agree, afsa, we have been diligent about painting and caulking these all wood windows which I believe were either Huddig or Huttig (a local company which sold out to another local millwork company) for about 10 years now. I'm just tired of fighting against the elements. Every year I have rotten sills and rotten brick mold in the lower corners of the windows. I even had my painter remove the tracks that hold the sashes to caulk and paint behind them where water was obviously penetrating. The sashes are warping and the gas seals are failing, and worst of all there's wood rot in the sheathing below the windows behind the stucco . . . again!! I don't know if this is primarily a window problem, an installation problem, a stucco problem, or some of all, but my experience with all wood windows has not been good to say the least. Hopefully, new windows, installed and sealed properly will keep my home from becoming a bigger money pit! With all that we have spent on maintenance and repairs, we could have paid for at least half of our new windows by now. I a hopeful to find a solution :-)

From the photo - That is not black trim. That is the storm window frame with a black accent paint around it. I can guarantee you that when you remove the storm window, the fin of the aluminum window beneath it will not be exposed. With vinyl siding, it is NEVER correct to install exterior trim on top of the siding. I don't know what your original siding was, underneath the vinyl. Do you? But with aluminum windows, I can almost guarantee you that the siding butts up against the window frame. IF there was a casing trim of some kind, it was most likely removed when the vinyl siding was installed. You remove the storm window. Then you remove the sashes/glass and mullions (if any) from the window, leaving just the frame. Then you pry the frame into the opening, pulling out the nails. You also hope at this point that the vinyl "J" channel was not nailed through the window fin. If so, the "J" will come off with it. When the frame is out, you then have the opening you will be dealing with. You can have the new window made to slip between the "J" and cutting back the sheetrock, or you can have the new window made to fit sheetrock to sheet rock, and trim the outside appropriately. You'll be able to see where the studs are, and the window cannot be bigger than the rough stud to stud opening. The problem is the vinyl siding. I hesitate to recommend cutting that back. Perhaps someone else here has a suggestion on how to do that without risking cracking/chipping and ruining the siding. The other problem with cutting it back to reveal the window fin is that you no longer have the right "J" channel - though maybe they can find some and slip it around the siding cut. But then you also cannot nail it properly after the fact. This is why I recommend leaving the "J" and siding alone. What abosolutely MUST be done in your situation is that the proper drip cap/flashing MUST be applied above the window. It must go up behind the sheathing, and turn out over the window, extending past the "J" channel, and then a downward bend of app 1/2". In your case, you have to have someone custom bend that on site. The addition of vinyl siding will make any pre-made drip cap unusable. It must start from up behind the sheathing or original siding, NOT the vinyl siding. Also make sure that the new windows are fully injected around the frame with low expanding insulating foam. This will be an absolute must for your application. That's probably clear as mud. But I did my best for you. Keep in mind, this is a standard every day job for any competent window company, and I did thousands of windows like this that never leaked. But if you get a crew in there that takes short cuts and depends on caulking for shedding water, you're going to be in big trouble down the road. Hope that answers your question. What the other guys here said is more true than you can know. "Contractor" guys are clueless about this kind of stuff, and it shows in the end results, and we've seen it a million times. I also want to tell you that if you chince on this, you will get a chince result and look. The money has to come out of somewhere. You don't want it to be the product or the workmanship. Pay for a good job done right, and you won't be doing it again in less than 10 years. Ignore this advice, and you will. It's not an insult to your intelligence, which I'm sure is adequate. It's just the fact of it. And unless you do this for a living for years, you cannot know, and I don't mean to offend, but that's the reality.

I'd recommend looking at JELDWEN's Siteline EX product. I used to sell Marvin's for years and still do once in awhile. In my area, I sell almost 7 figures a year in JELDWEN windows. I can say that their quality is near Marvin's and is 30% less. They also have a color called "Artic Silver" which looks like clear anodized but is an applied finish. Anodized coating SUCK as they scratch easily and cannot be touched up. If you don't believe me, ask your dealer what they warranty is on anodized product. If they don't say 5 years or less, ask for it writing prior to ordering. Artic Silver is a 10 year warranty through JELDWEN(20 years if you look at their Custom series product, which is equal to Marvin). As for Hurd, if they're close to the same price as Marvin I would pick the Marvin if you're not interested in JELDWEN. Hurd is a crappy brand name and what's the point of buying "knock offs" if there's not enough savings to justify it? I don't go to the flea market and expect to pay 10% less. My advice, look at JELDWEN's Siteline EX product. If you don't like the quality, buy Marvin. Find a GOOD dealer in your area that knows what he's doing and you feel you can work with. Call the manufacturer and see who they prefer in your area(they'll give you their best dealer who buys the best). Lastly, remember pricing isn't everything. One mistake can easily suck out what you saved by "shopping around"...