One of the many nice things about buying on a roll is you have less crinkling to undo. It's definitely an inexpensive way to go. The down side is the larger up-front "investment," which for most people limits the variety of battings you can buy.
I love Hobbs 80/20 and Hobbs Poly (6 and 9 oz)... I buy from
http://Heartbeatquilting.com. If you go through them, make sure and CALL for shipping costs. Their web site is connected to PayPal, which understates the shipping.