Haven't had any personal experience... but some pretty knowledgeable peoples had comments about Pyrithrin sprays here:http://boards.cannabis.com/hydroponi...rin-spray.html
same here regarding the ingredient Piperonyl Butoxide:http://boards.cannabis.com/plant-pro...bug-bombs.html

I would suggest you read this:
Quote Originally Posted by stinkyattic
Pest control:
You may encounter pests in your grow at some point, thrips and two-spotted mites being the most destructive, but prevention is simple. The oil of the Indian neem tree, has, among others, the property of being EXTREMELY distasteful to common garden pests. A spray made of one teaspoon Neem concentrate (Green Light brand is OMRI listed for organic farming) per quart spray bottle, with lukewarm water and a drop or 2 of dish soap, makes an effective (but smelly!) preventative spray. Trust me, use the neem. You don't want mites. They are pure evil. Mist lightly once or twice a week, never to the point of runoff, as overapplication CAN suffocate the plants. You will see that the neem has adhered when after a few applications your plants take on a more healthy, glossy appearance. Never apply neem after the 3rd week of flower, as it can leave distasteful residues on your buds. If pests DO appear, there are several options at the grow shop. I prefer bug bombs, set off 4 days apart, to kill pests. Pyrethrin sprays are also wonderful and very safe to use. Again, allow plenty of time before harvest when you are using chemicals on your plants. If you have an insect problem, do NOT flower until you are confident that it is under control.
I had very good results from Green Light Neem oil concentrate. Those little buggers haven't been back since. :jointsmile:

Hope that helped... Good Luck :thumbsup: