I pay all of my bills through my free online banking account site. If a company does not accept electronic payments, my bank will send them a check, and I don't even have to pay postage! I even have my kids' after school and summer program set to be paid this way. It's easy to manage, since I don't have to remember a bunch of different site logins or passwords, and many do an ebill that is connected to my online banking.
I also like it because i do not wait for a check to be cashed. I simply choose a 'deliver by date', such as for my rent on the first of the month, and my account is automatically debited on the day that I choose. I've never had a check deliver late (ususally they deliver early!)
As others have said, I would never do automatic withdrawals for paying a bill. This is completely differewnt. I like to be control of the withdrawal dates.