Agri-Fos Disease Control Systemic Fungicide

Has anyone used Agri-Fos for powdery mildew? The guy at my local grow store said it should work, but he wasn't 100% certain. He says it's a new product they've only had for a month or two, but by means of a Google search, it seems pretty popular or well known. If it does work, it would be excellent because I live at the beach and constantly battle powdery mildew.

If you have used it and/or know of it, please let me know what you think about its toxicity. My store only carries organic or non-organic pesticides/fungicides that aren't harmful for vegetable plants and such. However, they did say this one should be flushed before harvesting the plant's pot. So, that concerns me just a touch.

Any input will be appreciated. Spot treating a bunch of plants with Neem Oil in the flowering stage is a bitch. Thanks.