Hmmm... I buy TOTW for $48 per 30lb bag at my local store. (I think the lamb formula is a few dollars more expensive, but I rarely buy it... therefore I'm not sure I'm correct about there being price difference.)
Anyhoo, from my experience I would say that $70 seems pretty steep for that brand. Are they factoring in shipping or something?
As for the others... I have no clue. LOL! Sorry.