Well I've talked to a few farms and it looks like L'ancentre is the best bet since they selectively choose the *most* grass fed cows to make their butter from. I've had good experience with their butter before so I will continue to purchase theirs... And by most, I mean the cows in which the vast majority of their diet is grass with the least amount of supplementation.
A buddy of mine in Ontario says he can acquire grass fed butter so I'll poke him to figure out what brand it is -- maybe we can figure out a way to get it up here...
Living the primal lifestyle and loving it! On a constant quest of optimal health and living life to the fullest :-).
You can have excuses or results -- not both.