Complex sentence: The result was a lightweight, cheap to produce and highly mobile infantry anti-tank weapon though more exposed compared to the conventional "panzerjagers" of which construction cost many times an RSO/PaK 40.
Split into simpler sentences: The result was a lightweight, cheap to produce, and highly mobile infantry anti-tank weapon. It was more exposed compared to the conventional "panzerjagers" of which construction cost many times an RSO/PaK 40.