[Dagger2]

There's almost certainly more data in each entry than just the IP addresses, so it won't be 8x. NAT also requires a second set of entries to track the NAT session, which further equalizes it.

[gerdesj]

Absolutely. A state is protocol, ports, addresses, timers, counters and more. QoS/DSCP, firewall marks and other things add to the fun.