WRT120 and 160 work good enough but he might as well spend a little more for drastically improved reliability, more features, more onboard memory, and better 3rd party firmware options. That’s why Liam recommended the WRT54g v4 or earlier, their native firmware required more memory which means you can load a much better 3rd party firmware than the v5 or higher which had half the memory. The WRT320 has twice as much memory as the WRT160N.
WRT320s never crash, and by never I mean ours has been going for over a year now without a single error-related reset.