Independent side-by-side comparison of Onlythebestaas and Peptides 4 Research — third-party lab grades, tested purity, COA availability, FDA warnings, and community ratings.
Bottom line: Peptides 4 Research holds the stronger independent lab grade (ungraded vs D); Peptides 4 Research shows higher average tested purity (99.5% vs 98.0%); Onlythebestaas has more published third-party tests (11 vs 2).
Every figure below is either measured by an independent laboratory or read from the vendor's own website, and the source is named against it. PeptideAtlas is not affiliated with either vendor.
Onlythebestaas: 11 independent Janoshik assays, across 11 substances, median measured purity 98.0%, most recent 2022-01-21. Peptides 4 Research: 2 independent Janoshik assays, across 2 substances, median measured purity 99.5%, most recent 2025-12-29.
| Attribute | Onlythebestaas | Peptides 4 Research |
|---|---|---|
| Independent lab grade | Not graded | D |
| Third-party tests | 11 tests, avg purity 98.0% | 2 tests, avg purity 99.5% |
| COA available | Yes | No |
| Endotoxin tested | No | No |
| FDA warnings | None on record | None on record |
| Substance | Onlythebestaas | Peptides 4 Research |
|---|---|---|
| METRIB 500mcg/tab | purity not reported (1 assay, latest 2022-01-21) | Not tested |
| PRIMOACE 25 Mg | purity not reported (1 assay, latest 2022-01-02) | Not tested |
| TRENACE 100 Mg/ml | purity not reported (1 assay, latest 2021-10-08) | Not tested |
| Raw Powder "cialis 1G" | 98.00% (1 assay, latest 2021-05-21) | Not tested |
| TRENACE 100mg/ml | purity not reported (1 assay, latest 2021-05-15) | Not tested |
| CLOMID 50mg/tab | purity not reported (1 assay, latest 2021-05-15) | Not tested |
| ANADROL 50mg | purity not reported (1 assay, latest 2021-04-15) | Not tested |
| WINSTROL 50mg | purity not reported (1 assay, latest 2021-04-15) | Not tested |
| ANAVAR 50 Mg | purity not reported (1 assay, latest 2021-04-15) | Not tested |
| TESTOLONE 10 Mg | purity not reported (1 assay, latest 2020-11-13) | Not tested |
| Yk11 10 Mg | purity not reported (1 assay, latest 2020-11-13) | Not tested |
| Cjc-1295 NO DAC 10MG | Not tested | 99.27% (1 assay, latest 2025-12-29) |
Onlythebestaas. Onlythebestaas: 11 independent Janoshik assays, across 11 substances, median measured purity 98.0%, most recent 2022-01-21. Peptides 4 Research: 2 independent Janoshik assays, across 2 substances, median measured purity 99.5%, most recent 2025-12-29. These are third-party Janoshik assays published against the vendor, not the vendor's own certificates.
Full profiles: Onlythebestaas, Peptides 4 Research.
Full lab-test records: All 11 Onlythebestaas lab tests, All 2 Peptides 4 Research lab tests.
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