I don't use smart-connect. I prefer to set my devices to use one band or the other (only my old stuff gets 2.4; anything modern goes on 5).
W/r/t channels: for 2.4, I agree: use 1, 6 or 11.
For 5gHz, I am actually partial to the DFS bands because I'm in a low/no-radar area and no neighbors have hardware that can use UNII-2/UNII-2 Ext channels. So I get those to myself. Others find that to be too risky - leading to unexpected channel change, but I have a solution for that.
If you are in an area with low/no radar risk, then I'd recommend the UNII-2 channels, but I'm probably an outlier being a fan of DFS channels.
Note: some devices (Roku, Amazon) don't pick up DFS channels, so you'll need to decide if the trade-off is worth it.
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For the record, my solution is to be notified if radar is detected with this cronjob, which checks the log for the word radar and then emails me using the
div-email
script described in the
vnStat-on-Merlin thread.
Code:
cru a radar_detect "7 4 * * * grep Radar /opt/var/log/messages | /jffs/scripts/div-email.sh 'Radar detected - check channel'"
Note: I then need to manually restart wireless via the gui. I tried using adamm's
channelhog
script but found that the commands embedded in his script did not respect the channel selection in the gui, they simply restarted the 5gHz radio on whatever automatic channel had been selected. Completely as intended but not fit for my purposes. Besides it's only happened once in three months, and that was quite likely a false-positive.