Note that I deliberately wrote in that piece: "According to Apple, the drive and controller cards are not compatible with Macs with FDHD ROMs."
Presume my words to mean "that's what Apple say". Without exhaustive testing on a variety of hardware, it is impossible to say whether any device is compatible. When System 7 launched, Apple dropped support for some legacy hardware -- in order to avoid testing -- and declared it to be incompatible. That doesn't mean that it will fail to work all of the time.
The only time that you should totally accept advice about compatibility is when it is accompanied with words about blue smoke or data loss.