Why doesn't Virgin Media release a revised SuperHub 3 but with a different chip inside instead of that Puma one? You can then offer customers a replacement free of charge if they are not happy with the SuperHub 3.0...
Actually there are not so many DOCSIS 3.0 chipsets.
Basically you only have two alternatives - from Intel (Puma) and from Broadcom.
However, Broadcom chips are currently banned in Europe (or maybe Germany) due to court ruling (Broadcom lost infringement case). Considering that Liberty Global (who is now owns Virgin) wants to have single gateway device shared by all subsidiaries, and they have plenty in Germany and Europe - this leaves Puma only chipset choice.