XenServer 6.0 to 6.2 – Pros and Cons – Upgrade or Start Newly

I currently have 2 XenServer hosts running with version 6.0, not really any patch installed. They are currently pretty much maxed out memory wise. I was planning to add a 3rd host to the pool but haven't done it yet due to silly things that happened in the last year or so.

But I am now ready to add my 3rd host to the pool and now I am wondering what to because I would like to upgrade to 6.2.

Currently, I have 3 licenses for the Advanced options of 6.0. I have the DVS vm running and the two servers are running ovs. I have a iSCSI storage with all the VMs setup with multi-pathing (2 links).

Recently – a couple months, I started having occasional problems with the servers whereby the network connectivity stops for a moment and then comes back. DVS graphs show a sudden drop to 0 packets and after a few minutes, a huge surge and then goes back to normal. My switches don't report any problems. /var/log/message on the XenServer host shows lots of message of disconnection, time out, etc with ovs-vswitchd and then a command issued to reconfigure the network.

While I want to resolve this network connectivity issue, I am mostly mentioning it because it may weight in my upgrade plans.

So basically what I am trying to resolve is:

Should I add my 3rd server with 6.0 installed and then do a rolling upgrade (as at that point I will have enough resources to do so)?

OR

Should I setup my new server with 6.2, using the same iSCSI central storage. Then move some VMs to it enough to free up one of the 2 existing servers and then reinstall that one from scratch to 6.2 and then move the VMs from the remaining 6.0 machine and upgrade that one. In other words, start newly?

What would be best, providing all the above situation (old unpatch 6.0, network issue).