Smell was the biggest issue I had to keeping things stealth. You COULD put things in your grow room to cover smell, but what about the smell in the yard? That, and putting ozium, ona gel, and other things in your room could possibly change the odor/flavor of your babies, could it not? Trust me, wether or not you can smell em now, you will be overpowered should you not take precautions. You COULD be growing a strain with little smell, then again, you could be growing the dankity and that cop walking by costs you more than the best filters money can buy. I guess it all depends on your paranoia and location. First thing in the morn seemed to be strongest time for my babies too.