I don't really like the RS3M 2020. Needs lube to feel good, but many have difficulties lubing it without slowing it down. Heavy lube for springs, as it is the cube with most spring noise issues. And I use weight 0.01 (100cSt) for tracks, and weight 0.1 or 0.4 (1k or 4k cSt) for pieces.
Currently I main the GuHong V4M, some people have managed abuse it such that the center pieces breaks. I like the GTS3M and Meilong 3M as well. QiYi MS I rank lower than the Meilong 3M. RS3M is OK but not great. Tengyun V1 and V2M feels different. I can solve them with ok speed, and less corner cut noise than many others. The GuHong V4M gives pretty loud sound when you corner cut too hard. YLM I do not like.
And BTW, most cubes will feel better after a lube job, but you need different lubes.