PRO: The collar did spray when he barked.CON: The spray is very faint, you definitely can't feel it (I was hoping it would actually squirt him). It's just a subtle lemony scent. Which makes me wonder what impact the unscented version has.*Also, if your dog is on a barking tangent, then you can run through the supply in the collar in a couple of minutes.*Once the can only has about 1/4 left, it doesn't fill the reservoir anymore, so the last 1/4 or so is wasted.OVERALL: I think if your dog really hates the smell of lemon, this could definitely work for you. My dog didn't care at all and I went through a few refills pretty quickly (which gets pricey).A side note: Mine leaked a few weeks in and the manufacturer replaced it without any problems.