Within the Meisterstück line, the models laid out as cartridge pens are the small 114, the slim 144, the 145 and the 147 Traveller. The large 146 and 149, by contrast, are piston fillers and draw their ink from the bottle. Anyone who sets store by being able to change a cartridge quickly while out and about is well served by the first group, but forgoes the wide choice of bottled inks.
More important than the filling system, when buying, is the size. The 144 is very slim and sits unsettled in a large hand; it is in a sense the counterpart to the 149, the biggest and thickest model in the range. Since barrel diameter, weight and nib width have a considerable bearing on writing comfort, a pen should be taken in the hand and tried out before it is bought. That applies particularly to second-hand buying: a pen won at auction whose size or nib width does not suit one's own handwriting tends to end up unused, and changing the nib afterwards costs extra.