I picked up a new 2011 27 inch iMac 3.4 I7 with a 1 TB hard drive, 1 gig video card and 4 gigs of RAM refurbished from Apple for $1869 - a saving of $330 over new. I have a refurbished MBP for 4 years now, so I didn't feel the need to go new.
I ordered 8 gigs of after market RAM and installed them in 1 minute and now have 12 gigs. I also picked a 3 TB 7200 rpm FW 800 hard drive for back-ups.
I had a chance to play with Aperture 3, NIK and CS5 using my 5DII files. All I can say is that I am happy with the speeds. There is zero lag time between any adjustment brushed in Aperture, NIK or CS5. Essentially you press the button for the brush and it works - period. This machine is super snappy from what I had - 15 inch MBP at 2.4 core duo and 4 gigs of RAM.
I did a migration assistant from the MBP to the iMac using the FW 800 drive. It was simple and easy. The iMac is virtually the same as the MBP - everything was set up identical to the MBP using the migration assistant - right down to the bookmarks, dock, etc.
I did notice at 4 gigs of RAM on the iMac that I was getting the ball of death, but followed this and it cleared it up immediately: http://support.apple.com/kb/ht2409![]()
You can download OnyX and do an automated cleanup with everything checked (except for browser cache if that matters) and it will re-index everything by default. It also cleans up a lot of clutter - just don't run a full cleanup job more than once or twice a month. Even then, it's doubtful you'll gain much by doing so since OS X likes to learn about your habits.
