--- Quote Start ---
EPCS ID check can be disabled in jic generation. Isn't that sufficient?
--- Quote End ---
You would think that would work. However, whether I checked this option or not, the Quartus programmer would give an error about the ID.
The fact that Altera seems to make it difficult and does not officially support using 3rd party serial configuration devices is a bit of a turn off to me. With Xilinx, they even have recommended alternatives to their configuration devices. In a cost sensitive application, being able to use a much cheaper 3rd party configuration device is a significant factor. Having no official support for this can be a bit worrying.