Hello there, I'm trying to decide between the Astro 1442 or the Astro 1452 rivet nut setter. The latter being more heavy duty with larger setting capacity. 1442 appears to have capacity from M5-M8 and 1452 capacity from M8-12. Has anyone found a need or use for rivnuts bigger than M8? What rivnut size has anyone used to install supports along ribs for a transverse bed? Much obliged!