| Feature | ON Gold Standard 100% Whey (899g) | MyProtein Impact Whey (1kg) |
|---|---|---|
| Price | £20.86 | £24.99 |
| Rating | 4.6/5 | 4.3/5 |
| Protein per Serving | 24g (32g scoop) | 21g (25g scoop) |
| Calories per Serving | 120 kcal | ~103–113 kcal |
| Cost per Serving | ~£0.72 (~29 servings) | ~£0.62 (~40 servings) |
| Protein Type | Whey isolate/concentrate blend | Whey concentrate |
| BCAAs per Serving | 5.5g naturally occurring | 4.5g naturally occurring |
| Third-Party Tested | Informed Choice certified | Not certified (standard version) |
| Flavours Available | 13 | 40+ |
| Weight/Capacity | 899g / ~29 servings | 1kg / ~40 servings |
| Warranty | Standard Amazon UK returns | Standard Amazon UK returns |
ON Gold Standard buyers on Amazon UK highlight consistent mixability and genuine chocolate taste, with many citing years of loyal repurchases; the main gripes are occasional tub seal issues and price creep between restocks. MyProtein Impact Whey Vanilla reviewers praise smooth texture in milk and the wide flavour selection, but several note a synthetic sweetness when mixed with water and batch-to-batch inconsistency.
For most home gym users buying at these list prices, ON Gold Standard 100% Whey edges ahead: its isolate-first formula is gentler to digest, it carries Informed Choice certification, and the Double Rich Chocolate flavour is enjoyable enough that you won't need 40 alternatives. That said, if you're not competing in tested sport and you can catch MyProtein on a sale code, Impact Whey at sub-£0.40 per serving is almost impossible to beat for sheer volume and flavour variety.
ON Gold Standard best for: competitive athletes in drug-tested sport, gym users prioritising protein quality and digestibility over flavour variety, and anyone wanting a reliable no-faff daily shake. MyProtein Impact Whey best for: home gym enthusiasts who rotate flavours regularly, calorie-conscious users tracking daily intake tightly, and savvy shoppers who bulk-buy during Impact Week discount events.
At £20.86 for 899g (ON) versus £24.99 for 1kg (MyProtein), both products deliver approximately £0.030 per gram of protein — they are effectively neck-and-neck on pure protein economics, so quality, taste, and certifications should drive your decision rather than price alone.
The standard Impact Whey carries no Informed Choice or Informed Sport certification, meaning contamination risk cannot be ruled out for tested competitions. ON Gold Standard 100% Whey is Informed Choice certified and is the only safe choice of the two for athletes subject to anti-doping controls.
ON Gold Standard consistently rates better for water-only mixing: its isolate-first formula dissolves quickly without clumping and maintains flavour quality without milk. MyProtein Impact Whey Vanilla performs well in milk but can taste thinner and more artificially sweet when mixed with water alone.