Supporting 802.11g means scans are send at 1Mbit. 802.11a bumps it to 6Mb/s, so not much better. This means that every time you want to send a beacon you have a

Supporting 802.11g means scans are send at 1Mbit. 802.11a bumps it to 6Mb/s, so not much better. This means that every time you want to send a beacon you have a pause equal to the duration it takes to send a packed at 1-6Mbit, not to mention scanning all the channels.