Hi Chris,
In normal situations, no problem of running both radios.
You may use one or both radios depending on your requirements. When you do the site survey however you need to do a specific site survey of each radio if you'd like to use both radios because the RF spectrum for 802.11b/g differs than 802.11a. The reason why is that each use different frequenty range.
HTH
Amjad
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