I got this to try with my adult dogs, some of whom have a problem with marking in the house. It is a very very difficult habit to break no matter what you do.
I do believe this product deterred them (though did not stop) from marking in the same spot again. This product combined with a good cleaning procedure and proper training should assist many. If you have adult dogs with a long standing problem, there is no over-night fix. This is simply a tool that can aid you.
I find this product to have a very nice smell to it that doesn't bother me at all. I gave the product 5 starts, even though my dogs are still marking, it comes down to it being a complex training issue, and this is just one piece of the puzzle. If you have a problem with marking, this is worth a try. It would likely be highly effective in a young dog that does not yet have strong habits.