I've had my LHBS crush grains and it sat for a couple of weeks before I used it...no problems here!
Wrecked Brewery - "Prepare to be WRECKED!"
Primary: Ginger Saison
Kegged: Rasputin's Beard, Wild Strawberry Blonde Ale, Full Monty IPA
"Beer, it's the best damn drink in the world." -Jack Nicholson