I'm quite torn about brown vs white blocks. I myself use white (just salt). Brown has mineral in it besides salt. While horses suppose to lick as much as they need, I've heard the stories on my local forum when horses were done with the brown block in day or two. Plus I do add min/vit supplement, so I don't really need any extra.
As for S feed, I can't think of any. :) Strategy may be? That's pretty popular around here.
"Life isn't about waiting for the storm to pass: it's about learning to dance in the rain..."
"When we are no longer able to change a situation - we are challenged to change ourselves."
"How people treat you is their karma; how you react is yours."