This is exactly my build too. 4x MLas are too hot and the beam duration is slightly too long to keep focused on the enemy most of the time. The 4x SPLas build doesn't have enough firepower and the 5x SPLas build doesn't have enough weight capacity to also equip 2x AMS. I feel this mech is the best balance between beam duration and firepower without sacrificing any of the much needed defenses.