ABS and ASA have similar mechanical properties, though ASA is more stable and generally better. I do not use these plastics when printing firearms parts because of there poor mechanical properties. The tensile strength tends to be low, and layer adhesion can be very poor without a heated chamber. ABS / ASA does have the advantage of good heat resistance at low cost. Because of this I think it has potential as a low cost alternative to Nylons while also having good heat resistance. So I don't disregard the material completely, but I do think there are better options. PLA+ is better in all respects save for heat resistance.