Optimum Nutrition Serious Mass Protein Powder High Calorie Mass Gainer vs Serious Mass Cookies & Cream 2.73kg

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 mixability (mentioned in 3 of 4 reviews)
• ✓High calorie density (1,250 kcal per serving) supports rapid weight gain for hardgainers
• ✓50g protein per serving aids muscle protein synthesis and recovery
• ✓Added 3g creatine monohydrate per serving (evidence-based for strength and muscle gains)

Cons

• ✗Extremely high sugar content (12g per serving) and 250g carbs may cause energy crashes or GI distress in sensitive individuals
• ✗Not third-party tested or certified (no NSF, Informed-Sport, or banned substance screening listed)
• ✗Contains common allergens (milk, soy, wheat, gluten) limiting accessibility
• ✗Very high serving size (336g per scoop) makes convenient dosing impractical; typically mixed with large volumes of liquid

Best For