I don't have a local shop, so I buy 10 pounds of 2-row, wheat, vienna, and munich. I replenish as needed. I also buy a pound here and there of specialty grain. I haven't completed my pasta mill yet, so they always come to me milled. I keep my grain in the box it came in, or a 7.5 gal open ale pail. I don't seal it up after I open it either, just a spin and tuck (if even that). My brew room is 52 at its coldest during winter months, and probably 65 or a bit more during summer months.
It may not be the most desirable, but my schedule doesn't leave a concrete brewing possibility for the future, so it is more of a brew on a whim. I'm sure that fresh products would be most beneficial, but I do what I can.
From my records it appears that I ordered crushed wheat on April 26 that I didn't mash until December. It truly produced my best brew in the 10ish AG brews that I've completed.