The ease of use for our customers to access their account information is by far my favorite feature! I wish it could be easier or more intuitive at times but that's how you know your product really works well!! It has made billing so much faster with less errors than using excel sheets (and yes we used Excel before). We also have been able update invoices in real time now which saves us from having them sent out multiple months later when they are overdue if there were any issues during production/delivery etc..