The ABE re-gassing involves welding a valve into the top-mount of the shock. I think you also get a new, re-engineered central strut (which is hidden on the Dommie shock anyway) and new seals throughout. I will report back when I know how the 'new' shock performs. I kept the stock spring for now.
On my XRL I had a 20% over spring on the rear, and Wirth heavy springs in the forks, with thicker oil. Worked like a charm, and as a bonus the setup I had wasn't rock-hard when I was lightly laden (accompanying a 4WD, which was carrying my luggage was an example of when this paid off). I think on the Dommie I will leave the stock springs in for now, but install thicker oil.
The weight of a metal tank with stock volume is probably the same as a 20-odd litre plastic tank, and my rallye dash is much lighter than standard clocks. After some off-road playing I'll report back.