I know most here do the aftermarket RAM, but leaving that aside, the $800 difference between going with 32 and 64 gigs for RAM is startling. I'm planning on maxing out the GPU and the i7, but wondering if for my needs, 64 would be overkill. I'm a TV editor (we use old Mac Pro towers at work) and plan on using Avid Media Composer and eventually Adobe for editing indie films at home on my new iMac (it'll be my first personal Apple desktop), often from 4K sources (though I tend to transcode down to lower rez for editing). I'm not a heavy graphics guy, but I would love to learn color correction and try my hand at After Effects. Is there any reason, if I'm not a hardcore gamer or CGI artist, to go for 64 gig RAM? I'm assuming, also, that a 32-gig iMac can be expanded to 64. However, do we know yet whether an iMac ordered with 16 also will come with enough slots to upgrade up to 64 gigs? I appreciate any responses!