The recovery-peptide field is defined by how far community enthusiasm runs ahead of the research. These three are the most discussed, and ranked by evidence quality they separate more than the hype suggests, with the newest and most heavily marketed sitting last.
All three are healing and recovery peptides, and all three share the category's defining trait: the human evidence is thin to absent. TB-500 comes out ahead on research quality, with somewhat broader preclinical work in stronger journals, which is enough for Limited. BPC-157 lands at Weak, its enormous community following well ahead of its controlled human data.
Pentadeca Arginate is the one worth watching. It is marketed as a BPC-157 successor, an "upgrade" with a similar healing story, and it is the newest of the three. But it scores lowest, at Insufficient, precisely because there is almost no research on PDA specifically. The reputation it borrows is BPC-157's; the independent evidence base behind PDA itself is nearly empty.
That is the honest orientation for this category. If you are choosing by research quality, TB-500 is the best-evidenced and PDA the least, with BPC-157 in between, but the whole cluster sits low because none of them has the human trials that would move it up. The gap between the marketing ("proven recovery") and the evidence ("mostly preclinical") is the single most useful thing to understand here.
None of this says the compounds do not work. It says the research that would tell us has largely not been done yet, and that a newer compound wearing an older one's reputation, as PDA does with BPC-157, deserves particular skepticism until its own evidence catches up.