Both wil put little micro scratches in the clear coat over time dulling the clear coat somewhat. Get a magnetic bag, it is much easier to mess with.
Also, order a TankSlapper kit which is clear plastic and applies with water and can be peeled off if you want to remove it later.
www.tankslapper.com. They have kits precut for the Bonnie. Not expensive, about $17 as I recall. That will stop the dulling of the clear coat.
Monte