WAN Packet Size Performance Tuning w/ v5

[b.thoele]

So you have been using Veeam with off site jobs over a VPN or other WAN link and now you can adjust packet size.

Now what?

In a previous post there was talk about fine tuning ESX to send a packet with a more effeicent MTU size.
http://www.veeam.com/forums/viewtopic.php?f=2&t=908

One of the first steps was to determine your max packet size using ping. In my case on a Windows box I ran
ping –f –l 1400 hostx to determine my max unfragmented size is 1400 bytes.

When I go into my Veeam host properties under the Data tab I see the default "Packet Size" is set to 64 KB

What method do I use to determine the best packet size setting for this off site host?