Tallest cliffs, by falling duration If you threw something over a certain cliff on a moon of Uranus, it would take over ten minutes to hit bottom.

By this measure, local fall time rather than absolute height, what are the near contenders to the prize for tallest cliff on a body in hydrostatic equilibrium in the solar system?  Throwing the object horizontally at a few meters per second is ok.  Not ok is throwing it beyond a tiny body's Hill sphere.  Cliffs, not spheres.

Simplifying assumptions about atmospheres and exospheres are ok.
Let's apply @uhoh's answer's equation to a few bodies.  Numbers come from the obvious Wikipedia pages unless otherwise stated.  G = 6.6741e-11, in kg-m-s.

Verona Rupes on Miranda.
f = 20 km / 236 km, ρ = 1200 kg/m^3.  So t = 711 s.

Enceladus has rifts 1 km deep.
f = 1 km / 252 km, ρ = 1600.  So t = 133 s.

Those are the two bodies with smallest mean radius, of all solar system bodies in
hydrostatic equilibrium.

Let's try a much smaller eccentric body, just to check.
The nucleus of the comet Wild 2 has cliffs "hundreds of meters tall" (Ulivi's "Robotic Exploration of the Solar System," part 3, p. 228).
f = 200 m / 6400 m, ρ = 600.  So t = 610 s.

So Miranda's Verona Rupes beats even a comet.  Compared to Miranda, any other round body is much bigger (f is much smaller) and significantly denser (ρ is bigger), so to beat this it would need truly brobdingnagian cliffs, which flybys would have seen by now at least with radar if not with visible light.

I could grind through rest of that table of bodies in h.eq., but it's a safe bet that Verona Rupes wins by a long shot, Enceladus is a distant second, and everything else is a giant hardly differentiated peloton.