I think this deserves additional thought. If you could purchase a mining rig for $10 that could crank out 1 BTC/day, would it not be safe to say the value of bitcoin would be lower than today? I think this is the case.
Let's now approximate what it would cost to buy such a set of ASIC systems today. Maybe $75,000? $100,000? More?
And if that's the case, would I be foolish to sell the BTC it produces for less than $100,000/that number of bitcoins? That would be below my break even point once you factor in electricity costs.
I think there's no escaping the fact that miners control the supply, and therefore have a very big say in what we pay for BTC.