I just recieved my D10 to day and love it, but the piston drive is alittle tough to push. Is this normal? I thinks its due to the factory grease because its so think and sludge like that its creating too much friction between the wall of the piston drive sleeve and body of light. I also noticed that AW14500 batteries are alittle bigger than normal AA and sort of limit the travel of push to cycle threw modes. Normal?