Agreed, most users on the zt forum are very nice and you can ask anything you want without being called a jerk if you happen to say the wrong thing.
Anyway, another very important factor is AES encryption using hardware offload. Without this, the CPUs will be loaded to 100% due to software encryption regardless of how many cores and threads there are.
I haven't tested yet if hardware offloading for AES encryption is enabled with the new zt version v10.0.3 that comes with RoS 7.9rc.
The 4011 is a great router, but its performance is disappointing on v7 (CPU pegged on mine just downloading/routing, which never happened for me on v6). That, and it's a weak ARM chip in the grand scheme of things. The 5009 is a major ARM revision is this regard overall. Without offloading, a cheap Celeron appliance will perform much better and do much more.
@Larsa, I don't think it is. I am using ZT in Mikrotik and haven't noticed a difference in performance, but that might be also the fact that it is single threaded...
@Moba, agreed... It is unfortunate that we cannot squeeze a bit more of performance from RB4011 in this scenario. How I wished there was a version of the RB5009 with WiFi (and proper WiFi Wave2 for both nics).