is this actually a FULL cartridge? I am just wondering if we are comparig apples to apples when comparing this to the brand name, which sells for four times as much

Yes this compatible unit has same amount of toner gram weight as original. Even if you get 10% less than original, you are saving tons. If you want to go one step higher we have Xerox brand compatible and IBM brand compatible (Xerox and IBM makes compatible toners for HP and Brothers). Those should be under related product tab.