Well, answering my own question from earlier in the thread for anyone interested in Remote Play with The Division and how it plays.
Ubi have done an excellent job with regards to the config for the control scheme.
L & R shoulders buttons are as you'd expect - aim and shoot with the left and right side of the rear touch pad being for your skills.
Down on the D-Pad is sprint which works well with the left stick being so close to it. The D-Pad button can be pressed with ease while your thumb is on the left stick to initiate the sprint.
The front touch screen has the following commands:
Bottom left = The gestures like wave/surrender/call for help
Bottom right = Zoom on scopes with holding the shoulder button or melee attack
Centre = Bringing up the map
As for play-ability, I did afew missions on Hard and got through them fine albeit slower than I would on the TV with the DS4. I'm a little slower at aiming/precision and did have to turn the sensitivity down a little as I found my cross hair moving past enemies too quickly probably due to the smaller screen.
PVP however I did struggle. As I said I'm slower at accurate aiming with the Vita so when I was chasing a rogue down I just couldn't get the killer shots off on target or quick enough. When I had a Rogue going after me, I was down within seconds as I just couldn't react quick enough or even actually see him until I'd lost most of my health.
So IMO, remote play works and plays very well for PVE but I'll be avoiding PVP as I just couldn't get the accuracy and quickness required to return fire adequately.
This is after just acouple of hours on it so I'm sure I could get better at it as I adapt to the control scheme and smaller screen. It's also handy going around the BoO to the vendors and crafting etc if you don't have access to your TV but want to get afew things out the way before starting a mission etc.
2 quick off screen pics:
For anyone unsure about it, I'd definitely give it ago.