The data goes from the physical server directly into the management vNIC on the VM host. It doesn't bounce through the Vcenter server, so I don't think that's playing a role in the performance (or lack thereof).
You may look at this thread. Vmware added SSL encryption to Vmware converter by default starting with v5.0. Apparently you can get a big speed boost by disabling it if you don't need encryption. Considering we are usually talking LAN to LAN traffic, I think it's probably safe for most to disable it.
However, I still had an 800GB VM take several hours, so don't expect that 2TB volume to happen too quickly.
Do you have a dedicated VM/server for the vCenter Converter?
In my experience, conversion would take around 20GB-50GB per hour - depends on the used disk space too.
See also this KB on how to increase the speed of conversion: VMware KB: Increasing the speed of conversion when converting a physical or virtual machine using VMware Converter …Bayu Wibowo | vExpert NSX, VCIX6-DCV/NV1 person found this helpful
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vCenter V5.1 is running as a virtual on the Malaysian VMware farm.
vCentre V4.1 is running as a virtual on the Melbourne VMware farm.
I didn't see any difference when running a P2V on either so it looks like it IS dependent on where the destination host is located.