After a lot of Google searches, I'm looking at these:
Trendnet TWG-BRF114
Netgear FVS336G
TP-Link TL-R600VPN
Cisco RVS4000
I welcome comments on above, or recommendations for better ones! I absolutely require a wired model (no wifi, bluetooth, etc.), must have gigabit WAN, NAT & SPI, and must 'just work' with Ubuntu or Debian.