New iMac. I'm not so sure this time.

I went the other route. I removed my optical drive from my MacBook Pro and replaced it with a 500Gb hard drive. I replaced the drive that came with the MacBook with an SSD drive. I put the removed optical drive in a USB enclosure. The once or twice I use the optical drive every few months does constitute a problem to have to plug it into the USB port. BTW the SSD drive does the start up in about 15 seconds. PhotoShop CS6 loads in about 5 seconds. To top it off the MacBook runs about 35 degrees cooler with SSD as  startup drive. I store all my image files on the 500 GB drive and have a very efficient setup. It's like having a new much more useful computer.

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http://photo.net/photos/Michael%20Eckstein