AMD has called DDR5 6000MHz C30 to be the "sweet-spot" for AMD DDR5 RAM. According to the B650M AORUS PRO AX QVL list, this RAM is indeed Hynix M-Die (the 2nd best for overclocking behind Hynix A-Die).
https://www.guru3d.com/news-story/ddr5-6000-memory-is-the-sw…
This is also backed by the fact that all reviewers were given the same 6000MHz C30 RAM sticks.
So, I guess if you're looking for the DDR5 RAM sticks to keep for the foreseeable future at a reasonable price, this is it. Could also probably OC to 6400+ MHz easily if that's your style.
This is the cheapest 6000MHz sticks around based off my research, it even has CL30, which is significantly better than anything remotely near this price, usually around the CL36-40 range.
BTW, Hynix A is the best