I'm about to buy a Mac Mini and have got the DIY Fusion Drive parts handy. I'm actually a bit on the fence about the choice of manual SSD+HDD separation with the aid of symlinks and proper Fusion Drive. Both have their pros and cons.
What worries me though are a couple of articles at Mac Performance Guide:
The author claims that he's not able to make the migration of frequently used data from the HDD back to the SSD to actually happen, placing blame on the fact that he's using a 3rd party SSD.
I haven't seen reports of this sort of problem anywhere else on the web. Has somebody here running a 3rd party SSD in a DIY Fusion Drive on a 2012 Mac Mini been able to actually verify that the data moves both ways, SSD -> HDD and HDD -> SSD? I mean real, hard proof backed by
iostat or some other method proven to be valid.