Now in Asda's almost everywhere. There is a list on their site: http://www.quorn.co.uk/~/media/Quorn/Do ... s_PDF.ashx
They also mention Tesco - but not Waitrose, so they are rolling it out slowly.
I've tried both products, I've never eaten quorn before so wasn't sure what to expect.
It's OK, nothing to shout about. The texture of the 'pieces' is very soft almost as soft (and flavourless) as tofu - I expected a bit more texture and hoped for more taste. The burgers are OK, there isn't much flavour in the quorn itself (so at least it's not offensive, unlike some gluten products) it's all in the coating.
Worth a go and good if it becomes easily available.
I'm most pleased to see them openly responding to an increased demand for vegan food - let's hope it continues.