Compare Air Fryers
Granitestone Big Boss 16Qt Large Glass Air Fryer scores higher on safety - here's why.
The most important dimensions, side by side.
The crisper plate base is aluminum without food-grade certification. Scores 4/10.
The racks are stainless steel but the specific grade (304, 316, 18/8) is not disclosed. Likely food-safe but unconfirmed.
Ceramic nonstick coating -- PFAS-free not confirmed for this model. Ceramic coatings can chip and degrade.
Glass bowl and bare stainless steel racks -- nothing to chip, flake, or degrade.
The basket is bare aluminum. Source says aluminum without food-grade qualifier.
The glass bowl is tempered glass. Food-safe but less chemically inert than borosilicate glass.
This model claims PFOA-free only -- NOT PFAS-free. PFOA is one compound in a family of thousands. The TurboBlaze model explicitly claims PFAS-free; this one does not.
Granitestone claims the product is free of Teflon and forever chemicals. Glass + stainless inherently lack PFAS, but no third-party testing published.
Square basket design for optimal crisping and airflow.
Glass bowl with halogen, convection, and infrared heating provides 360-degree cooking.
1500 watts provides strong, fast cooking with good temperature recovery.
At 1300 watts, preheating is slower than higher-wattage competitors.
Full temperature adjustability for precise cooking control.
Temperature adjustability not confirmed in sourced data.
Basket is dishwasher safe for easy cleanup.
All removable parts including the glass bowl go in the dishwasher.
55 dB from Cosori -- near the quietest tier in Tom Guide testing.
No noise measurement published by manufacturer or any independent lab.
2-year limited warranty from Cosori.
Standard 1-year limited warranty.
Good value at $89.95 for a 5-quart mid-range air fryer.
$129.99 for 16 quarts of zero-coating glass + stainless steel cooking.
Everything you need to make the call - who each one is for, and who should skip it.
Go for it if you...
You prioritize cooking performance -- 1500W with square basket and quiet 55 dB operation.
You want a dishwasher-safe, 5-quart capacity from a well-known brand with 2-year warranty.
You are comfortable with ceramic-coated aluminum and understand it is PFOA-free only, not PFAS-free.
You want good value at $90 for a mid-range air fryer.
You want a large-capacity (16 qt) glass air fryer with zero coatings at a mid-range price.
Dishwasher-safe parts (including the glass bowl) matter for easy cleanup.
You want the glass bowl convection cooking experience with halogen + infrared.
The main thing to know
This model only claims PFOA-free, NOT PFAS-free -- a critical distinction. PFOA is one compound in a family of thousands. Both basket and crisper plate are bare aluminum without food-grade certification. The ceramic coating introduces a degradation pathway. Safety is the dominant scoring pillar and these material choices constrain the overall rating.
The Granitestone Big Boss uses tempered glass and stainless steel racks with zero coatings -- strong material safety. The stainless steel grade is unconfirmed (generic, not 304). ETL certification is referenced in Amazon text but not independently verified.
Skip this if you...
You want PFAS-free food-contact surfaces -- this model only claims PFOA-free, which does NOT mean PFAS-free.
You want uncoated food-contact surfaces -- look at glass or bare stainless steel air fryers.
You require third-party verification of any chemical-free claims.
Material safety is your top priority -- bare aluminum and ceramic coating score below average.
You need confirmed 304 or 316 stainless steel on food-contact surfaces.
You want independent PFAS verification beyond manufacturer claims.
You need independently confirmed UL/ETL certification.
Neither of these quite what you're looking for?
I've reviewed all Air Fryers options at every price pointEvery Air Fryers in our database is scored using R3's deterministic scoring system - the same inputs always produce the same score. For this comparison, we evaluated Cosori and Granitestone across 3 independent criteria: Safety (90%), Efficacy (7%), Usability (3%). No sponsored rankings. No paid placements.
Straight answers - no sponsored content, no filler.
The Cosori Pro LE Air Fryer 5-Qt uses a bare-aluminum basket with a bare-aluminum crisper plate. PTFE-coated nonstick may contain trace PFAS compounds, which is reflected in its 3.8/10 safety score in our scoring system. For a PFAS-free alternative, look for models with stainless steel or borosilicate glass baskets.
Between these two, the Granitestone Big Boss 16Qt Large Glass Air Fryer (borosilicate glass basket, 7.7/10 safety) uses materials I'm more comfortable with at high heat. The Cosori Pro LE Air Fryer 5-Qt's bare-aluminum basket scored 3.8/10. In our scoring system, basket material accounts for a significant portion of the safety pillar, which is our highest-weighted scoring factor.
For families, capacity comes first: Cosori offers 5-qt vs Granitestone's 16-qt. Overall, I'd lean toward Granitestone for most families.
304 stainless steel is inherently PFAS-free and won't off-gas at any cooking temperature. Nonstick coatings (PTFE/Teflon) are stable below 400°F but can begin degrading above that threshold. In our scoring system, stainless and borosilicate glass baskets consistently score higher on the safety pillar. That said, a well-maintained nonstick basket from a reputable brand still meets safety baselines - it's a question of margin, not danger.
R3 uses a deterministic scoring system - the same inputs always produce the same score. We evaluate each Air Fryers across Safety, Efficacy, Usability using independently verified data. No sponsored rankings. No paid placements. Every score is fully reproducible.
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