How we evaluate longevity hardware.

Three rules of buying longevity hardware

1. Single-purpose beats multi-function. A great cold tub is better than a so-so cold-tub-with-sauna combo. Most multi-function longevity products underdeliver on every individual function compared to category leaders.
2. Warranty is the spec. A 1-year warranty on a $5,000 product is a tell. We weight warranty depth heavily. Cabin and chiller warranties get reported separately because they often differ.
3. Owners outvote reviewers. A product with 200 verified owner reports beats one with 12 magazine reviews. Our editorial team has visibility into clinic-patient and optimizer outcomes through MyProtocolStack that single-product reviewers don’t.

The scoring rubric

Deep-reviewed products receive a score from 1.0 to 10.0. Scores are calibrated against the category, not against the entire site - an 8.5 cold plunge is comparable to an 8.5 sauna in relative quality, not in absolute spec.

Per-category weighting (approximate):

• Build quality & materials (20%) - construction grade, sourcing, durability under expected use cycles.
• Performance against category benchmark (20%) - how it stacks against the category leader on the spec that matters most (e.g., for cold plunges: temperature stability and minimum °F).
• Warranty & service (15%) - cabin warranty, component warranty, dealer/service network depth.
• Value (15%) - price relative to spec, not absolute price. A $9K tub can score higher on value than a $4K one if its spec/price ratio is stronger.
• User experience (10%) - install complexity, ergonomics, daily-use friction.
• Brand track record (10%) - years in market, installed base, founder transparency, regulatory standing.
• Smart features / ecosystem (10%) - app quality, integrations, programming flexibility.

What disqualifies a product

We will not include a product in the Vault if any of the following is true:

• Brand makes medical or outcome claims that aren’t backed by published research at the dose / use case sold.
• Warranty is shorter than 12 months on hardware over $1,000.
• Brand has been the subject of FTC, BBB, or NAD enforcement on affiliate disclosure within the last 24 months without remedy.
• Product is sold primarily through paid-influencer promotion with no editorial review presence.
• Brand requires affiliates to use specific marketing language that overstates outcome claims.

Pricing freshness

Every product’s price field carries a verifiedAt date. Prices are re-verified against the manufacturer’s page quarterly. Promotional discounts (subscribe-and-save, founder pricing windows, multi-bottle bundles) are noted in the price description but not factored into the displayed range unless they represent the standard buying path.

Editorial firewall

We earn commission on most outbound product clicks (read the full affiliate disclosure). Editorial scoring and ranking are walled off from commission economics. Specifically:

• No paid placements. We don’t accept money to feature products.
• Higher-commission programs don’t rank higher. Our top-ranked sauna pays under 10%; we recommend it anyway.
• We disclose commission ranges per program on the disclosure page.
• When a product we previously recommended drops in quality (warranty cuts, brand issues, regulatory action), we update or remove the review - even if it’s an active commission source.

Updates and review cadence

New products are added on a rolling cadence. Existing reviews are re-verified quarterly for pricing, warranty terms, and brand standing. Major product updates (new model release, brand acquisition, FDA action) trigger an immediate review revisit. Spotlights and deep reviews carry a publishedAt and updatedAt date so you can see how fresh the editorial is.

Found something we got wrong? Email ryan@lifespanvault.com with the page URL and what we missed. We update reviews when the facts change - corrections are visible in the updatedAt field.