For over a decade, microstructure imaging has been a hot research topic in DW-MRI. Tissue complexity compelled researchers to make assumptions about certain properties. The inverse problem of microstructure imaging, in particular, is ill-posed, and current methods fix some parameters to reduce the solution space. In this abstract, we look at how intracellular and extracellular diffusion coefficients affect the estimation of compartmentalized model parameters. We show that robust estimation of some parameters does not extend to all parameters using Monte-Carlo simulations in impermeable substrates with multiple diffusivities, and we identified the extracellular compartment as the most influential on estimation quality.