The OP wrote above:
[[ Imac will be mostly used for Lightroom 5, PS, and some cubase/kontakt .
I want this computer to last me for about 5 years and I'm wondering if the extra $500(including tax) for flash storage even makes sense. Any advice? ]]
My advice will be different from others' on this forum.
Instead of paying $400 extra, I would suggest this:
Buy the 3.2ghz with the 1tb HDD for the lower price.
Buy a "bare" SSD of your choosing. You can find 240-256gb SSD's out there now in the $120-130 price range if you shop carefully.
Buy either an external enclosure like this:
http://www.amazon.com/MiniPro-Exter...34&sr=8-3&keywords=oyen+digital+2.5+enclosure
Or... buy a USB3/SATA docking station like this:
http://plugable.com/products/usb3-sata-u3
(disclaimer: I have no financial association with the above products)
Now, do this:
1. When the iMac arrives, set it up as you normally would.
2. Put the drive into the enclosure or dock and initialize it using Disk Utility
3. Download CarbonCopyCloner, free to download and use for 30 days
4. Clone the OS/apps/data from the iMac to your external SSD
Let the external SSD become your "external booter". Even though it's USB3 (not thunderbolt) you will be AMAZED at the boot and run speeds you get from it.
Also...
You should consider partitioning your 1tb internal HDD.
Make the first partition the size of the SSD. Let the second be whatever space is left.
Now, "re-clone" the contents of the external boot SSD back to the first partition on a regular basis. If you do this, you will always have an instantly-bootable backup of your OS/apps/accounts, etc.
You can use the second partition for scratch storage, or as an "archival volume" (containing things you wish to keep that would otherwise "clog up" your boot drive.
If you wish, get another external drive to serve as a backup of your scratch/archive partition.
If you get an external dock/240gb SSD, you will have spent about $155 -- and you will now have a combined total of 1.25tb of storage.
If you spend $400 extra for the 512 SSD, you will have spent $350 more, for about 1/3 the total space...