Up until last week I had for roughly three years with at lest four different routers (I went through a phase of swapping routers until I found a good one for VoIP!).
No problems this way. In fact during this time I had the odd Airnet TiVo in for modifications making three on the network with no problems.
I had my two set up with static IP addresses (ie not DHCP) and of course made sure that the MAC addresses were different.
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