Kingston Fury Impact 32GB 3200 C20 (2Rx8) is what I am running my X25 beast (replacing the original 1Rx16 16GB kit that it came with - same as the Legion Pro in this regard).
Just checked and it looks like you can now get a 16GB kit of the same memory (competitor so cannot link) if you don't need 32GB. I am assuming that it has the exact same specifications as the 32GB kit.
EDIT: Just checked the data sheet and it looks like the 16GB kit is 1Rx8 so single rank vs the 32GB dual rank. Shouldn't make a massive difference as both are the faster x8.
Key thing is ensuring the memory is x8 and not x16 and supports DDR4 3200 @ 1.2v without XMP (not supported). The Impact kit has the advantage of having slightly tighter timings (C20 vs C22) without needing XMP.
In gaming I have noticed a small bump in overall performance which aligns with what others have seen.