Yep, the online service makes it a breeze.
And the mail process is what makes a bit slow. It's also better to get the bill via the internet since it sometimes gets lost in the mail and you might forget about it and end up paying the late fee
However, always write it down in your calender so you don't forget, and remember to check it online. You can do it both ways though, have it sent to you by mail, and still be able to read it online.