Spin against power, and how long each lasts
Raw carbon grabs the ball. That is what produces the heavy topspin drives and sharp rolls the material became known for, and it is why almost every premium paddle of the last few seasons uses it.
Composite and fiberglass faces are springier. They return more energy, which reads as power, and they grip less. Graphite sits between the two.
The part people miss is durability. Raw carbon's texture is what does the work, and texture is consumable. A composite face keeps behaving the same way for longer because less of its character depends on a surface that wears.
Why this is the key question on a used paddle
Face texture is tactile, not visual. A photograph shows scratches, which barely matter, and hides texture loss, which matters enormously. This is the single most common thing a private seller misrepresents without meaning to, because they genuinely cannot tell.
Run a thumb across the face. If it does not catch, the paddle has become a control paddle, whatever it was sold as. That is not a defect and it is not worthless. But it is a different paddle from the one in the reviews, and the price should reflect it.
Every listing here carries a grade that accounts for face wear, which is precisely because this is the specification you cannot check from photos.
Which to buy used
If spin is central to your game, either buy raw carbon at a high grade or accept that you are buying a control paddle. A heavily played raw carbon paddle at a low price is good value for a dinker and a disappointment for anyone expecting bite.
If you rely more on pace than shape, a used composite face is the safer buy. There is simply less to lose as it ages, and the value proposition holds up better across grades.