Might be best to grab the 4.
If you are like me and have a couple of files open in AC11, one doing a render or someting and annother you are working on, the extra ram helps.
I have a habbit of running out or ram on my intel iMac with 2 Gig, but it will only take 3 Gig anyway.
Cheers,
Karl Barker.
27" iMac 3.6 Ghz Intel Core i9
32 Gig Ram
Mac OSX 10.14.6
AC 5.5 - AC22 (NZE)