Guided Wave based SHM (GW-SHM) relies on the use of elastic guided waves to interrogate plates or unidirectional structures such as pipes for defects and has received considerable attention from the literature in the past few years. Despite a large number of in-lab setups and more mature prototypes, GW-SHM finds no high-maturity applications outside the pipeline industry. Indeed, the complexity of the GW propagation phenomena inhibits the demonstration of reliability of GW-SHM. In other words, in order to ensure the efficiency of GW-SHM system on real-life situations with varying environmental conditions and exploitation constraints, a huge number of experiments are to be conducted. In order to quantify the robustness and efficiency of the GW-SHM systems, dedicated simulations tools have been developed and released in the CIVA software. These tools rely on spectral finite elements and a dedicated meshing strategy to ensure fast but reliable computation. Compared to current commercial finite elements tools, computation times are reduced by 2 to 3 orders of magnitude. This communication presents the validation of such tools in GW-SHM configuration. Simulated signals are compared to experimental ones for both isotropic and anisotropic panels. Results of guided wave imaging algorithms are compared between simulated and experimental datasets.