Does 16 GB Ram increase performance by a large factor in the new MacBook Air?

i agree with Macjack that for today 8GB of RAM is sufficient but if you hope to keep it in use for 4 or more years it might be prudent to go with 16GB since there’s no upgrading later. The way each new version of the OS and new applications require more memory, I suspect we’ll be looking at 8GB as too little in 4 years.

it isn’t clear if you intend to replace the iMac with the Air or augment it. Either way, look at your data storage habits on the iMac. It looks like you have lots of media that could easily and conveniently be stored on an external rather than an internal drive. The cost of a 1TB SSD from Apple is huge compared to the cost of 1TB from a third party. In many cases a 500GB internal drive will suffice for applications and critical data along with an external for media and less frequently used data.

You didn’t answer FoxFifth’s question: what kind of software, what kind of tasks do you intend to do with the computer? For example, on my notebook I mostly browse the internet, write, develop program assignments & curriculum for my classes, and do minor editing of photos I take with my iPhone. For these tasks 8GB is plenty now and should for for the 5-6 years I intend to keep this computer. However on my desktop I do more involved photo editing, some video editing, and presentation work. When I create presentations I prefer to have all the applications involved in the process open at the same time so I really need 16GB of RAM.

Personally, I’d not upgrade any Mac, desktop or notebook, beyond 500GB. The cost of a 1TB SSD from Apple is huge and the inconvenience of using an inexpensive external drive too small to think otherwise.

It can help depending on what you are doing. 16 GB of ram should make your system more faster and smoother. For my MacBook Air, I just use 8gb Of ram and it works fine.

There are 2 things to keep in mind if you are replacing the iMac with the Air. Portables will take abuse that a desktop won’t simply because we don’t move desktops around the way we do portables. I’ve seen iMacs last incredibly long times; portables too but I’ve also seen more portables abandoned due to broken displays, spilled liquids on keyboards and so forth. Nearly any repair on a notebook is at least 1/3 the price of a new computer. Second, the butterfly keyboards will be warranted for 4 years but after that you are on your own. That’s a gamble I have chosen not to make.

Dont get me wrong, I love the MBA and I couldn’t live without mine. But I’ve always told people to buy a portable because that’s what they need, not because it’s what they want. My MBA is required for work but I’m almost certain this will be my last since I retire in 9 months.

What types of things are you planning to do with the Air? Knowing that may help someone give you a better response.

That depends on the apps you will be running. For just basic web surfing, word processing, photos, email, no. But I always like to have more RAM to future proof for needs you didn't anticipate and more modern operating systems which seem to use more and more RAM.

It seems like you need hard drive space more than RAM. For the applications you use 8 RAM is sufficient (16 better) but you could use a larger hard drive, probably a 1TB SSD. Or, you could move larger, lesser used files off to external media to make more space.