Yes mono blocks are one channel but you run two sumultaneouly for stereo.There is only one channel in a monoblock, as you may have realised.
a. Fosi offers the unusual option of a shared 10A power supply via a spliiter cable. Independenttly testing to see how the shared 10A compares to the separate 5A power supplies would be of interest to some.
b. More importantly to me, if you only test a single channel, you won't know if beat frequencies are generated.
My follow up questions to Amir were intended to see if there was a way to test for beat frequencies or if he considered them non-issues and/or not worth the effort to test (if a test was possible).