How do I verify my data size that will be replicated through VVR

I need to find a way to figure out the Mb/sec (Mb=Megabits) that will be replicated to my offsite and the pipe size I need in order to stay insync. I have been testing VVR and have all of my setting in place with everything working correctly. But with a 10Mb VPN internet pipe I have the line pegged at 10Mb all the time and am never able to catchup. When I looked at Performance monitor, Physical and Logical disks I am only generating about 4Mb/sec of disk writes which is what is being replicated the the offsite. Am I looking at the wrong data for my replication size needed? Is there a way to verify the Mb/sec that are going to be written the my offsite prior to starting VVR?

Thanks for the help.