actually I don't think that u need 16GB of RAM for the next few years of macOS and lets say mid level design processes. unless u really develop huge projects.
but than u would be experienced enough to know ur demand and should invest more than 600€ on ur money making machine...
with the specs of the retina 13" there is something wrong. either its a 2012 model (HD 4000) or it should be Iris 5100 for late 2013, which is much better.
comparison:
https://www.notebookcheck.net/Review-Apple-MacBook-Pro-Retina-13-Late-2013-Notebook.105035.0.html
the 15" will have more power. but portability and nicer screen on the 13" way better. personally I would go for the retina
I'm no expert but a friend of mine is a web designer. He spends his time in Photoshop, InDesign, Illustrator, various browsers, email, etc. and runs a VM for Windows compatibility testing I believe. He does fine with 24 GB, but 16 GB for him isn't quite enough. That's for his work. Others may need less but then again he says others might need 32 GB.
For the record, I am NOT a designer but use mostly just office applications with a few other things thrown in and sometimes there is a second user logged on (my wife) because she didn't bother to log out of my machine after using it.
I find that in that scenario, 6-8 GB is usually fine, but sometimes I need a bit more. And if I were to add in a VM - which I don't do now but which I have done in the past - then I'd want 12 GB or more. So, my iMac is configured to 24 GB and my MacBook is configured to 16 GB... and it sounds like my needs might be lighter than the OP's.
That said, for my kitchen surfing machine, even just 4 GB is enough most of the time, although occasionally it'd be nice to have 8 GB.
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I guess I'm saying is that you want
minimum 8 GB for anything more than very basic usage, but if you're a designer, it seems like the needs can jump significantly higher than 8 GB fairly quickly, depending upon your workflow.
[doublepost=1506030011][/doublepost]Note that while it's true that current versions of macOS feature memory compression, I do feel that doing a lot of memory compression may impact performance. I occasionally see slow downs even when the swap is not used. This is in times when significant memory compression is active. Add more memory and these slowdowns disappear. I suspect what is happening here is that with these old machines, the CPUs are slow enough that overhead from memory compression and imperfect memory allocation schemes can impact performance enough to be noticeable, even if you don't hit the swap file.
