While I can't comment on mvebu devices as I haven't tested them, x86_64/AMD64 devices can do "linespeed NAT" without a switch at all (mid-range ones with SQM at symmetric rates). Some have indicated that the mvebu devices has sufficient processor power to be able to achieve at least one-way, "gigabit" rates. Note that flow offload generally precludes use of SQM and hardware offload "always" does.
Edit: The Recommended Routers page you linked appears to be very out of date, though no fault of yours.
The best, concise summary of SoC information I know of is (ignore the thread title). Note that this was written before gigabit symmetric had started to penetrate the consumer market and "gigabit WAN" may refer to gigabit downstream only.