Bests & Worsts Reviews from Amazon

I have four cats and Advantage had stopped working completely. The house and cats were hopping with fleas. It was horrible. I vacuumed. And flea combed. And used various products in the house short of fogging which is impractical when you have four cats living there. The vet's assistant had suggested these collars as an option. Came to Amazon because the price was much better and I needed multiple collars. Then I saw the reviews where people claimed their cats died and developed horrible skin reactions. That was a bit offputting. I hesitated. But the fleas were very bad and the vet's office--which I trust--had recommended them. I ordered three collars, figuring that I'd put them on my healthiest youngest kitties first (ages 11, 7 and 4--weights 10 to 16 pounds) first. My 14 year old cat (6 pounds) loves to be combed, so I would just comb her. When the collars arrived I, for perhaps the first time in my life, read the package insert that discussed the company's trials of the product. The only notable side effect observed in testing (as I recall it) was some dermatitis. It wasn't a lot of the trial participants but it was observed, and this explains the folks whose cats lost hair. Encouraged by the package insert, I put the collars on the cats. Initially, I was afraid that one of them was getting lethargic. Then I decided he had always been that lethargic and I was just paying more attention because I was afraid I was doing something that might kill my cats. Ultimately, the only effect these collars had was killing fleas. It took a couple of weeks because the fleas had gotten so bad, but they went away. About 99%. And the cool thing is, they also went away on my one cat on which I did not put a collar. Just having three collared flea killing machines wandering the house protects my fourth cat as well. She gets the occasional flea, but it's rare. And while I used to comb her twice a day to get the fleas off now I comb her once a week and find maybe one or two. Which seems pretty unavoidable given that she and two of the other cats go outside. It's been about six months now so the collars are supposed to last another couple of months. Hoping that by December there won't be fleas around to kill and that I can wait until spring for the next round of collars. Great product. Less expensive than Advantage for comparable months of effectiveness. And works like Advantage used to work when it was new.