No subject

guarantee that any current or future 4-channel mics can be opened in the
4-channel mode using the "hw:CARD" device name. I'm just worried that
there might be cards that split the four channels to e.g. two stereo
devices, "hw:CARD,0" and "hw:CARD,1", and then "hw:CARD" won't work. I
might be mistaken, but aren't there some such cases with playback, which
have to be opened with the "surround" device names to get all the
channels?

The "surround" devices also guarantee some specific channel mapping,
which may not match what "hw" uses, which is another reason to prefer
"surround" over "hw", but I don't think this applies to input side.
Therefore, the only possible problem that I can see with "hw" is that it
might not provide all channels.

-- 
Tanu