Should I send my SAT or ACT scores?

Hi, future undergrad student here! I’m unsure if I should send my ACT scores or my SAT scores to colleges that I am applying to. I’ve heard multiple times that colleges prefer the SAT over the ACT and they only check the composite score for the ACT as where on the SAT they check all of the sections.
SAT Scores: First time I took the SAT: W: 450 M: 690 CR: 430
Second time I took the SAT: W: 510 M:680 CR: 550
ACT Scores: Only took once: English: 23 Math:31 Reading:28 Science: 25 Composite: 27
My question here is, should I send my SAT scores to show the improvement that I’ve made with the writing and critical reading sections or should I send my ACT scores? I am more willing to send my ACT scores because I have a higher math and reading subscore than the others although I am not sure colleges go that deep into reviewing the ACT. Any advice?