[pirocks]

My sibling comment has a lot of good info, but to answer your question for ddr5, SK Hynix makes the ram capable of the highest frequencies/best timings, Samsung is second and micron is third. At least this was true when ddr5 initially came out, these things could change. Its also worth mentioning that manufactures can have different grades/product lines so there is variation within a manufacturer to. My perception is that Micron and Samsung are cheaper than SK Hynix, though idk what wholesale prices actually look like.

[Strom]

In addition to generation, there are also differences based on capacity. I know less about DDR5 specifics, but with DDR4 you had Micron having the best chips for 32GB dual-rank sticks, while Samsung had the best for smaller capacities.