[LunarBerry]

They are alright, but after using them for awhile I find that they might work best for dogs that already have good teeth or mild dental build-up and would be good for maintenance. When they don't quite have the best teeth, they don't seem to do as much as I would like, in my opinion. My dogs like them ok at first but then they kind of got bored with them fairly quick, but may still eat them (just not with as much gusto) As for if they are actually healthy, I would assume they are decently healthy but like any other "snacks" it's best in moderation.
There was something else that I used from Milkbone that came out not to long ago that worked well (can't remember the name), but again, my dogs got tired of them, but may still naw on it some. ^^;; If your dogs loves them and they work well, then I don't see why not keep using them.