Fuel wise, it took a couple of fills to get the bags settled in the fuselage so they filled to their maximum. I used a large car engine oil extraction syringe pump to inflate and deflate the tanks before fuel was added- it has volume marks so I could see what was going into the bags. I then used calibrated bottles of fuel with 1ltr marks on them. I consistently get 2.9 ltrs in the two bags, on one fill with more pressure I got just over 3ltrs. Both these figures are greater than the user able fuel in an UF Evo tank.
I now extract all the remaining fuel and air from the tanks before filling with a conventional fuel station.