Recently, we have been experimenting with different products cleaning the hardwood floors. We've tested cleaning the floors with just plain water v. Murphy Oil, Dr. Bronner's Sal Suds, and Bona.
1) Murphy's Oil was by far the cheapest of all of the products. Especially considering that it is sold in concentrate and needs to be heavily diluted to clean the floors. If diluted well, it gives the floors a subtle sheen. If too concentrated, however, it leaves an unpleasant residue.
2) Sal Suds was the most expensive one, at $18/bottle. It is highly rated and supposedly eco-friendly (although the main ingredient is sodium lauryl sulfate). It has a pleasant smell, but we didn't notice any appreciable advantage in terms of cleaning quality compared to Murphy's Oil.
3) Bona was priced in between the first two products. It is readily available in most stores like Walmart, Home Depot, or Target. While it's a bit pricey, we found it produces the best cleaning results. Our floors were left squeaky clean and at the same time very shiny and beautiful.
Therefore, we recommend Bona as our current favorite for cleaning the hardwood floors.