Since I bought it two years ago, I have been quite happy with it. Although I would prefer a better design because it is a little bulky on the collars, my dogs don't seem to notice, so I'm good. I'd want to acquire an additional module (I recently added a second dog) and extra replacement straps in case we lose any. My only gripe is that there doesn't seem to be a simple way to accomplish this on their website. I called customer service, but I never heard back. I'm attempting to purchase your goods with my hard-earned money, but I can't just click a button to do it. Why is that? Why isn't the website home to these replacement parts? It seems like something really basic.