Is 4GB of RAM enough for a new Retina MBP? Today I have a new rMBP (bottom of the range latest MBP with 4GB RAM and 128GB SSD) coming and I've just found out that annoyingly they have an upgraded model out just £100 more than I paid, with 8GB of RAM and a 200MHz upgrade to the processor (which the latter I'm not bothered about). This is an upgrade to my 2012 Macbook Air 128GB, also 4GB, which I used for Xcode, Terminal, VIM, browsing the internet (same for the rMBA). I always look at my RAM to find that it's usually nearly full, but I don't have any issues what so ever (no slow downs, no crashes, no panics), and it never changes. I don't multi-task (I don't need to). The prime reason for buying a rMBA was for the Retina screen -- I could have got a MBA for the same price.

I would like to use this for 2-4 years.

My question is whether to get the RAM upgrade or not.
No it is not enough to have 4GB, since it is minimum you can have and you will always run at max of it.

Mavericks will do the best to manage the space, but there is a limit what it can do.

Big RAM users (aside of the OS) are the web browsers.

It is all dependent what is your activity, apps you use. As said Mavericks will do great job in working your RAM to keep it to a workable levels, but adding RAM can only help.

Here is an example from my MBA with 4GB.



And the top 10 totaling 1.5GB  (as you can see I do not run RAM heavy apps but do get over 4GB.



Yes, do the RAM upgrade, it is worth the money.