First things first i will explain my use.. 50% Music Production.. I have some pretty quality equipment that i want to record with and the imac is going to be my main workstation this stems from. I will be downloading alot of plugins to run through midi which i am not sure how much space that will take up. 30% Editing Videos.. Pulling images, videos, etc off the internet and using final cut pro to create videos. In this case i will be using adobe products such as photoshop and illustrator to help create content. 20% Downloading music, videos. Using a program to extract from youtube to an mp3. Storage does not need to be crazy big here... never gone over 200 gbs ever when doing this on past computers. 10% Surfing internet, emails, Microsoft word. My first question is imac 21.5 vs imac 27.. do i need the 27 to get great / excellent performance for what i am doing? in the past i have used macbook pros. IS their negative feedback to the new IMAC displays ? not sure if anyone feels this way or have past models looked nicer? As far as upgrades should i just get the stock 27" or 21.5" but premium stock and install the ad-dons such as ram, hard drive, sound card myself? will this be a way cheaper alternative and is it complicated? I really want to run a parallel as i need to have access to windows when creating music.. is this recommended? any dropbacks to running two platforms on an IMAC? is their a better way to do it ? I know these are alot of questions but would greatly appreciate any help!!!