The main advantage of the FS-50 over the FS-20 is that the FS-50 has a lower profile head to it, and fits underneath of furniture and cabinets easier. It also has an ergonomic D-shaped handle to it that makes it easier on your wrist while you’re using the steamer. In my opinion however, the FS-20 is all around their best product, this one has the capabilities of using a short handle for mattress’s, and also has a telescoping handle to it (which FS-50 doesn’t), and for the difference in price, and there’s no difference in the performance of the products, the FS-20 is the best buy for Haan. It also happens to be our most popular product.