Platinum is just the efficiency rating like gold and bronze but there's nothing wrong with getting a 1000w psu it will be under less stress than a 750w counterpart.
Semiconductors have to be reasonably good to not waste power into switching and conduction losses.All be it, to achieve Platinum efficiency they tend to use quality parts. So it's reasonable to assume they are good, but always do a bit of research before buying.
Semiconductors have to be reasonably good to not waste power into switching and conduction losses.
But efficiency doesn't limit capacitor choise, or using little tight sizing.
Silverstone does those mediocrities.The decent brands don't tend to do budget Platinum/Titanium option PSUs like they do with bronze and gold models.
The relative small cost saving they would make won't make much difference when you looking at the £100+ price ranges. Buyers at this level of the market are more likely to do research, so sticking in a few really cheap parts would likely be counter productive and cost them more in the long run. And they tend to have longer warrantees which they don't want to be used.