Personally, I wouldn't be too down on Sizzix if they sent me a replacement machine after I broke the first one by not following directions. If I broke a second one by -- again -- not following directions/cramming through too much material, I'd suck it up and figure out how to use the machine properly.
Yes, the Vagabonds require more strict adherence to the sandwich directions than the manual machines (also true of the BS Express). When you add an electronic motor to *any* machine, you are adding complexity that will increase the places/parts where things can go wrong.
Irritation that a machine that doesn't work properly and/or as advertised is one thing, but being upset at a company because their machine broke due to a customer not following directions -- twice -- is not warranted, IMO.