Just to say for those in Scotland (I'm not sure about the rest of the UK!) that Grahams Dairies butters are from grass (silage in the winter) fed cows, as confirmed by their Technical Director:

"All milk supplied to Grahams Dairies is from Herds that are farm assured which are from grass fed cows which are predominantly outside grazing but in the harsh winter months they will be fed on silage."

Whilst I do like the Kerrygold butter, it is a little heavily salted for my tastes, and this gives a further string to the bow for those who prefer an unsalted/lightly salted option.