Do you guys find the Fusion Drive to be satisfactory? I'm used to the speed of all-flash in an MBP, so I'm not sure if I'd like the Fusion Drive. What I really want is a setup like my Windows desktop: 160 GB SSD with the system and all my applications on it, everything is fast in day-to-day computing. It also has a 2 TB HDD that I store my lossless music and downloaded movies on. The only time I notice that HDD kicking in is when I go to listen to music or watch a movie. Otherwise, it's as if the computer runs only on SSD. But I've read some reviews of the iMac saying that things constantly jump back and forth between SSD and HDD and that over time as you fill up the fusion drive, it gets slower and slower. What has been your experience?