I would not do anything FusionDrive, not hardware and not software:
- unnecessary because the prices are close together,
- the FusionDrive software is already a long time "out",
- SSDs have a much longer lifetime than HDDs, thus you gain no lifetime against a hdd,
- the number of writes on the ssd-part is much higher when you use fusiondrive than when you use "standard" os, and thus the Garbage Collection must do many more writes,
- low efficiency because of the "housekeeping" actions by the OS,
- when you use a "hybrid" drive without the FusionDrive OS, it will not really speed up things.
- as you can see on the market, hybrid drives are out already a long time, but for one particular hybrid drive that is still available.
Lex