Should I get standard hard drive or fusion drive on a new 21.5" iMac?

Question

I'm thinking about getting a new 21.5" iMac.  How do I decide whether to get the standard hard drive (5400 rpm) or the Fusion Drive?  Besides Web surfing and email, I would be using it to play flash games, listen to Internet radio, and stream movies occasionally on Netflix. 

Answer 1

@TmanW:
Technically you cannot control where data goes on the Fusion drive 100% of the time as in the case of a two drive setup (SSD + HDD), but you can tilt where the data goes by watching disk usage and also partioning. My understanding how the Fusion drive works from MacPerformanceGuide.com (where they tested the Fusion on a late 2012 27" iMac) is that as long as you do not have more the 112GB filled on the Fusion, the drive won't kick data to the HDD when peforming tasks that use more than the 4GB buffer. I interpret this to mean as long as I keep the capacity below this 112GB threshold, I am more likely to get SSD performance. And to keep things under this threshold, one could just use the Fusion drive for system and apps only and perhaps targeted file usage (working Photoshop files that would be transferred back to non-SSD storage afterwards).
MPG also tested the Fusion drive with a partition method that biases the first partition to be 2/3 SSD and in this scenario a user can effectively (though once again not 100%) target SSD usage most of the time.
Once I get my new iMac, prior to cloning my existing system on to the Fusion drive, I will see firsthand if these tests are true to form with their results.