I have my bladder tanks.
The machine was returned painted and looking fine. Filler neck a little higher, and no more painted filler cap.
The tank kit did not include a new fuel guage, or re-calibrated dial face, so the guages showing in the cockpit are calibrated to the old volume. Though it is most likely that half-tank indication is still half a tank the US gal numbers on the guage are wrong and could lead to over-estimation of remaining range. This seems a simple thing to fix and it is silly, in my opinion, to add another "swiss cheese hole" that, one day, I am sure someon will line-up.
In addition, as we should not take the guages to be accurate we dip the tanks before flight. The tank kit did not contain a new dipstick, and the old one is going to over-read if used in the bladder tank. And as Arrj advised me recently, are you really going to stick an aluminium dipstick into a bladder tank? What have others done? Do I resort to making my own wooden dipper?