Thermal convection in solid planetary mantles is usually modeled with impermeable top and bottom boundaries. If a magma ocean is present above or below the convecting layer then mass can be exchanged between the solid mantle and the magma ocean. The dynamical boundary condition at the mantle-magma ocean interface becomes one where the normal stress is proportional to the normal velocity. In this contribution, we will describe the results of finite amplitude simulations of convection with this boundary condition in spherical axisymmetric and three-dimensional spherical geometry. When both boundaries are permeable, an extremely efficient translation mode is seen. Cases with one permeable boundary show boundary layer instabilities from the impermeable boundary only and have mean temperatures similar to the permeable boundary. Simulation results will be presented and implications for early planetary evolution will be discussed.