We use one - corded version and not especially for pet nails, so I can't comment on the exact version you're looking at but we love ours! It has lasted for years and we use it all the time and for a lot of dogs. It makes quick work of the nails, you get a nice rounded end, it's great for getting quicks to recede, and a lot of dogs seem to tolerated it better than clippers - especially true if their previous owners quicked them.
So, for us - definitely worth it.
So, for us - definitely worth it.