Numerical models do not consistently capture non-dipolar or tilted/offset field features. Global MHD models typically have options to include field tilt relative to the rotation axis, but rarely include offset or non-dipolar terms. Ring current models tend to operate using only northern hemisphere information and assuming a dipole field with some perturbation (e.g., the Tsyganenko family of empirical models or a force-balanced deformation of a dipole field), limiting the amount to which a fully realistic field is considered. This affects the accuracy of conjugacy/asymmetry adversely. Furthermore, the numerical solvers used in the global MHD models have a finite order of accuracy, which leads to artificial processes, such as reconnection. These terms are suppressed with a parameter called numerical resistivity. However, this process also undercut the MHD model performance in producing accurate open-closed field lines. In the recent years, MHD-EPIC (embedded particle in cell) models [Chen et al., 2017] have been developed to transition to a kinetic definition at regions that reconnection is likely to occur, which demonstrated a better performance to reproduce open-closed field line signatures.