buttons buy cart difference exact features important information interface list multiple offer payment paypal processors recommended support supported unlike

I noticed there are e-junkie cart buttons and e-junkie Paypal buy now buttons. what is the difference and why is e-junkie recommended?

They support all the features we offer, work with multiple payment processors, provide a nice cart interface, unlike buy now buttons.

Could you put an EXACT list of which features are supported with Cart and which features are supported with Buy Now?

This is important information.