I think we talked about this not too long ago. I agree with shibumiseeker: Rotate every 6 months to a year. I keep about 4 gallons under each sink in my house, which is more than enough to meet the immediate (72 hour) need. You always know it's there when you need it, but out of sight when you don't.
Heck yeah I would drink it. Better off to not stock up on too much water as it is hard to transport. Better to scout out water sources and spend your money on a good hand water filter pump!
The gallon jugs will develop leaks after time. ...