An IDEFix Express is what I have in my A1200 tower, where a dual CF card adapter is connected to the main port (2 + 8 GB cards), and a dual SATA adapter is attached to the second port. To the SATA adapter, I have currently hooked up a third CF card + a cable that goes to an external port. This one is used for connecting an external harddisk for backup purposes once in a while.
My desktop A1200 (custom case) has a regular IDEFix installed, where a dual CF adapter is connected to the main port (2 + 2 GB cards), and a slim CD-ROM drive is yet again to be attached to the secondary one. I had to disconnect the drive due to power issues, but I have now bought a more powerful PSU.
The IDE-fix 97 software is nice, although I find the documentation to be a bit lacking. One important thing to have in mind, is that it can be a good idea to use the IDEfixPrefs tool for disabling all unit numbers that isn't used by any device. IDEfix have a tendency to hang upon boot if this is not done. If disabling has been performed, it is equally important to remember about this, in case another device is to be connected in the future.
The IDEFix adapters are no longer available, but individual Computers have a tendency to make new batches of their old hardware if the interest is there (like the Buddha). So it is possible that new IDEFix boards may come some time in the future.
As for now, I do belive that a 4xEIDE'99 currently is the best available option.