The reason why I prefer N-only is to avoid any down-training of speeds if a G or B only device somehow gets on to the network.
This is a known limitation with a lot of wireless networks such as:
https://discussions.apple.com/thread...art=0&tstart=0
It's safer just to reject all non-N clients than to try and down-train the entire network to support the slowest client.
On some routers it's also possible to set the bandwidth to only 20MHz instead of 40Mhz. 20MHz is probably a good call in your best practices outline to prevent it from eating up too much of the airwaves.
Lastly, we've been using the old Linksys WRT610N that used to come in the FRC kits many years ago. These have proven to be pretty excellent routers specifically for this purpose, although I am sure there are much better, more modern alternatives now.
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