Hands down , the Infinity. In my opinion the pella impervia is not only cheap looking but also very flimsy. I dont know any pro’s thay recommend that window.

We are putting the Marvin Integrity wood ultrex in our house. I think they are a little cheaper than the infinity.

I did a lot of research on sound control and the tests show that laminated glass does not help much. Actually dissimilar glass thickness works better. Of course if the increased cost is not that much it's probably worth it.

I'm trying to remember who did the study, it was not Pella or Marvin, I think Jeld Wen. You can find the report on the website - extremely detailed but you will never equal the sound level of a insulated exterior wall with just the window (I think they provide sound levels of a wall for comparison or search). I assume that's why you also are going with STC.

I did not know about the STC's, I checked the website - can you tell me about how much these run?

I was going to replace all south facing windows on my house but on stucco house with trim the repairs are a real PITA and then paint entire house. For comparison though I did put in patio door. I have the typical double pane metal frame Vikings - absolute junk. I don't understand how these windows were allowed from perspective of efficiency standards on a 20 year old house. When we had our house pressure washed in prep for painting I had to follow the guy from the inside because water just poured in! Not only that but south facing Vikings get so hot in the summer you can barely touch the glass!

Anyhow, when I replaced the slider with a Pella with the highest rated thermal glass I could not believe the difference. Even after all day baking in the sun the glass is barely warm. And closes like a car door so I'm sure you will be much more comfortable no matter what you choose.

Laminated glass is less effective with regards to low frequency (like traffic/highway noise) in my observations. In those cases, additional air space thickness and offset glazing seem to work.

That said, laminated glass is absolutely incorporated into the design of dedicated STC windows. Whether we are talking about some windows at the airport or something like Milgard's QuietLine, Laminated glass is definitely used and is effective in those cases.

That is interesting feedback about the performance of the Low-e Glass. It really is quite amazing at how well it works which is why I challenge folks many times on the idea that they either shouldn't use it or the fallacy that a single pane window with a storm is just as effective.

Now if they would compare a single pane wth a new low-E Storm they would come close in thermal and should outperform in STC.

This is true. If the storm is a heavy glass unit or a laminated unit...absolutely. Air space is critical with highway noise (i.e. low frequency). They would also have a smaller appearance opening and the hassle of a storm too. Everything is a trade off in one capacity or another.

Even without the heavy glass or lamination in the storm the old window that is rehabbed and weatherstripped should out perform in STC and easily do so with 3/16ths glass and even mor so with laminated.

I agree. See the airspace reference above. My point was that if they are really going for high STC performance, they should opt for a heavy monolithic glass or laminated storm.

I found the article, for some reason laminated glass in a typical dual pane does not seem to buy you much at least according to Jeld Wen. It might be that it's too thin.

The article is a bit contradictory though first saying Dissimilar glazing can approach LG then saying LG has little effect. You can go to tech docs and see testing results but no LG results. I give them credit for doing all the work as I did not see this data on Pella or Marvin.

http://www.jeld-wen.com/en-us/products/windows/design-inspiration/about-windows/338-acoustic-performance-in-windows

At the MAC (airport noise)program here Marvin runs Storm windows with 3/16 glass. Renewal by Andersen had to do The same thing. In the beginning they were using laminated storm windows with single pane prime Windows. Marvin and Pella should be able to give you information you need, I just called there engineering department last week and they answered all my questions.