LP doesn't take stacks of quartz, but can take more space easily. It's more energy efficient and more flexible, but for large bases transport is slower and more laggy. Also, one of my favorite features, LP calculates how much of everything it needs before starting crafting, whereas AE only sends stuff to process when it hits it. For example: say I request a solar panel, and I have 2 silicon cells already. AE would send the cells to the blast furnace, wait for them to finish, and then send more sand to the electrolyzer. LP would see that it needs more cells, and then send sand to the electrolyzer and the cells to the blast furnace, effectively shaving off time.