HI,

for me its interesting because I have the accounting of differents countrys for differents companys, then you can use a different chart of accounts in every company.

regards

Well the option gives you the facility to choose a company on records. Like while creating a product, you can choose a company (by default it takes a current user company, but you can change if you want). Without enabling multi companies you are not giving access to your users and all the records by default stored on current user's company.

Also this option helps you if you want to share common records across companies. (if you want to share products for all the companies)

Hope, this may help you.