Why in the world are you using the condom fill method? That went out when soft caps came into play. Just pop the white tip out (and the inside o-ring if there is one) and drip down the sides. Do 4 or 5 drops, turn, 4 or 5 more drops, turn and repeat until you have about 20-25 drops in your carto. Much less mes than condom filling.
That being said, the ones I'm using right now are from Liquid Express. They pair up well with both my 3.7V
mod and my 5V
mod and this last batch I received seem to last forever.
Blank Xpress 510 Carto