I'm getting 10G easily with fasttrack, even without jumbo frames.
Here's more detailed performance analysis for more home oriented usage:
I think this really depends on config, I can also get my CCR1009 go with full 1Gbps with limited set of rules and fastrack disable, but once I add more complicate config it does slow down a lot, with some of my setup I cam see 2 of the core go to 100% while only 300mbps single tcp steam.
I think with 80+ firewall rules, 2 VPN connection and policy based routing using mangle 300~500Mbps for single tcp steam without fasttrack is acceptable, but well, if mikrotik can release a new routerboard with much faster core I will happily to replace the CCR.
I'm also using CCR1009 as vpn (ovpn) concentrator (lots of connections), several hundred firewall rules, several hundred address list entries, interface lists, PBR for management traffic, dual WAN with 3G attached using usb adapter, various HA monitiring scripts, EoIP with IPSec and buttload of stuff so it's probably hard to put more junk on it xD
The only things that really matters are:
- bridge (bridges heavily cripple performance)
- jumbo frames
other things are less relevant (unless you're talking strictly about encrypted traffic performance). If you use stateful firewall with fasttrack then whole firewall processing is negligible. If you need QoS then Queue Tree should work with fasttrack.
Basically you should be using fasttrack unless there's absolutely no way ever to do that (which is rare since most of stuff is doable with fasttrack enabled).
That said x86 also struggles with traffic processing without hardware acceleration. Eg. virtual networking even on i7 can drop down to 1gbps. If you're concerned about single stream performance then you can try RB4011. It should perform better in such scenario.