We consider the eversion problem for highly compressible hyperelastic thick-walled cylinders. We focus attention on two features of such problems that are not adequately described by standard analysis. We investigate, first, closure of the cavity for sufficiently thick tubes and, second, the instability of relatively thin tubes. We find that the closure of the cavity can be ascribed to the fact that actual foam cylinders behave differently in tension and compression. However, the instability of thinner cylinders seems to be governed by some other mechanism. In the course of the analysis, we show how exact solutions to the equilibrium equation for the eversion problem can be generated. Unfortunately such solutions are not compatible with the boundary conditions.