Hi All,
Here's my update as promised:-
Replaced V-Reg II with DVR2 yesterday, same wiring so a very quick and easy job, one out, one in! In the garage with bike on the main stand it took enough revs to move the bike backwards before the ammeter needle flicked to charge so went for a test ride up the road and back and was happy to see the ammeter needle flicking to charge when there was enough but not excessive revs.
Also LEDs were delivered yesterday so fitted those also. Tail light was just a simple replacement of the bulb. The pilot light was just a little more work because it has a rubber bulb holder so it doesn't make an earth like the original one - so there's two wires. Soldered on connectors and fixed the earth to one of nachelle bolts. Switched on lights and was amazed. Photos attached. As you can see the pilot light, which apparently only consumes 1.5v is far brighter than the 38W dip - and even lights up the garage.
So, in conclusion, in my opinion it was definitely worth doing.