[cisco-voip] Upgrading CCM 6.1/Unity 4.x/UCCX 7.x to UCS/8.x/Unity Connection

[Chase Voisin]

I've got a large CCM 6.1.5 environment composed of 5 servers, most of
which will not support CCM 8.6 in production (bridge upgrade only).  I
have a project to migrate our existing CCM servers, Unity (4.x) and
UCCX (7.x) into a new UCS chassis outfitted with B200 blades.

I've been given two differing paths to take.  My SE has recommended
that I perform a BAT export from the existing environment and a BAT
import into a clean new 8.6 UCS install for the CCM piece and a direct
upgrade to Unity Connection in UCS.

>From what I've read and been explained I can also choose to use
Cisco's disaster recovery tools and perform a restore to a new Cisco
demo depot server for my 6.x environment.  Then I can  upgrade from
6.x to 8.6 on the demo server.  Finally I'd stand up a new 8.6 server
in UCS and restore the 8.6 from the demo server to the UCS chassis.

Which path should I take in this process?  There is a lot of hesitancy
in going from 6.1 to 8.6 directly in my environment due to the "large
number shift" and the perceived un-safeness of moving 2 major versions
forward.  Should I be concerned that I'd be moving two major versions
forward?

Also, to migrate from Unity 4.x to Unity Connection I'd preform a
COBRAS export from the existing Unity environment and import the users
into Connection.  Are there any additional steps that I'd need to take
into consideration for the migration?

For UCCX as I understand it, it is a simple backup of the existing
server that must happen then I'd stand up a new 8.x UCCX server and
restore the existing 7.x backup file to the 8.x server.  Can you tell
me if there are additional gotchas to it?