Have just started to use their e-commerce features and agree they are awesome. By comparison I have just built an e-commerce site using BigCommerce and it has been a chore using their site builder. Also have a Shopify site on standby, but I think Weebly will end up being my site of choice, mainly because the guys listen and make every effort to accommodate the users.
Gator Website Builder has more than 200 templates that are professionally designed and available for free. And yes, all of them are mobile design compatible. You don't need to do anything to activate the mobile design. Gator does allow you to edit the content in your mobile version without affecting the desktop version. Editing content on the mobile version can be handy if you have special mobile-only sales or if you want to optimize the experience people have on their phone.