Marcinkiewicz CH E3.1FLJWM vs Marcinkiewicz 3FLS
The Marcinkiewicz 3FLS has a wider cup diameter, the Marcinkiewicz 3FLS has a larger throat opening.
Cup Diameter
The Marcinkiewicz 3FLS has a cup diameter of 17.93 mm / 0.7059 in compared to 17.12 mm / 0.6740 in on the Marcinkiewicz CH E3.1FLJWM — a difference of 0.81 mm / 0.0319 in. A wider cup generally produces a fuller, darker tone but requires more air support.
Cup Depth
Both mouthpieces share a medium cup depth, so the sound character from depth alone will be very similar.
Throat Diameter
The Marcinkiewicz 3FLS has a wider throat (4.39 mm / 0.1728 in vs 4.32 mm / 0.1701 in). A wider throat allows more air through, increasing volume and projection but reducing resistance.
Which is better?
Neither mouthpiece clearly dominates the other — the right choice depends on your embouchure, playing style, and the sound you're after. Try both if possible.