Optimum Nutrition Serious Mass Protein Powder High Calorie Mass Gainer vs Critical Mass Professional Lean Mass Gainer Chocolate 2.4Kg (40 Servings)

Pros

• ✓Highly effective for calorie surplus and weight gain, with multiple reviewers reporting measurable mass gains (e.g. 2 stone in 3 months with training)
• ✓Strong long-term loyalty — several reviewers report 5–10+ years of consistent use
• ✓Good flavour profile (strawberry and banana rated as milkshake-like)
• ✓Excellent calorie density (1,250 kcal/serving) makes it practical for those who struggle to eat enough food

Cons

• ✗Inconsistent quality between batches — at least one reviewer reported a virtually flavourless delivery
• ✗Mixing challenges: oversized scoop won't fit most shaker bottles, and blender is often needed to avoid clumping
• ✗Digestive discomfort (bloating, gas, heaviness) reported by multiple users — typical of high-maltodextrin mass gainers
• ✗Premium price point relative to own-brand alternatives, though most reviewers consider it justified

Best For

Pros

• ✓Excellent taste and smooth mixing (all reviewers noted this)
• ✓1,000+ calories per serving supports lean muscle gain efficiently
• ✓Well-tolerated by beginners and sensitive digestive systems
• ✓Good value for price point (noted by reviewers)

Cons

• ✗Not third-party tested or certified (no banned substance verification)
• ✗High calorie density may not suit users with smaller appetites or cutting phases
• ✗Only 4 reviews available; limited sample size for reliability assessment
• ✗May contain added sugars typical of mass gainers (nutritional label not provided)

Best For