I have found ticks this winter as well. I found one on a dog that was staying with us after a foot of snow fell the night before and it had been under freezing for weeks.
I use Frontline still. It does not repel ticks, but kills them within 12 hours (I think). They can not contract Lime until 18 hours+. I don't use Advantix because you can't use it on cats and it makes me nervous even that the cats are around something like that. Plus, if you can't use it on cats, I worry how good it could be for the dogs. The tick collar that my vet once recommended was not able to be used around cats either.
I believe it takes 24 hours for Frontline to use ticks, and it USED to be believed that this was soon enough to prevent Lyme. We now know this is not always the case. Plus, it doesn't prevent the massive site reactions that some dogs (including Kodi) get from the bite itself. In our case, we started off using Frontline, but the number of ticks we have made it less than optimal. Kodi was coming home every day with 10-20 ticks, some still crawling, but others embedded. We had to do something different.
As far as cats are concerned, that is a problem for the first 24 hours IF your cats play with the dog. (mine doesn't get close to him if she can avoid it!
) But after 24 hours, it is safe. You need to keep them separated for 24 hours if you use Advantix for dogs. (there is a separate formulation that is safe for cats)
ALL of these products contain toxins, and there is ALWAYS a possibility of an unexpected negative reaction to ANY of them, whether it is Frontline, Advantix or flea collars. (for dogs or for cats) This is equally true of the feed-through stuff like Comfortis (for fleas... it doesn't work for ticks).
In terms of (canine) Advantix being less safe for dogs just because it isn't safe for cats doesn't follow. Different species have different sensitivities to different chemicals. Deet is the most effective chemical for keeping mosquitoes away from people, and is generally considered safe if used correctly. Deet is a neurotoxin to horses, which are a MUCH bigger animal. Conversely, the chemicals used in bug spray for horses are not safe for humans.
I think that it's important to coordinate with your vet in terms of what types of insects are the greatest risk in your area, and what products are the best deterrents, based on your property and your dog's life style. (a dog who only walks on city streets has much less exposure than one who runs through long grass on a farm) Also mention the other animals in your house (you can't use "flea bombs", for instance, if you have either birds or fish) and the presence of small humans who might have contact with the products. (you don't want your toddler chewing on the cat's flea collar!!!) Then with ALL this information, you make an informed decision based on what's best for your family and pets.