I have a preference for wired solutions. I have no practical experience in using multiple repeaters. Single radio repeaters store and forward the data on a single channel which means the data throughput is cut in half for each "hop". They also operate on the same channel as the originating AP which means you could have 2 or more repeaters in close proximity trying to transmit on the same frequency at the same time and this could cause interference and loss of data. I presume the software used in " mesh" networks reduces the possibility in their networks.
You didn't say how many people actually try to access the network at the same time, if only a max of 50 do have you considered just adding another WRT54G with external antennas and connect both WRT54G'S to a wired router for your Internet access? You could run one on channel 2 and one on channel 10 and split the traffic that way.
Which version of WRT54G are you using? Have you considered using 3rd party firmware on it as it can improve a number of options including QoS?
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