Luke to be honest theres not a lot that can go wrong with them,if the pump goes it`s about fifty quid to put right and if the battery packs up there about £25.When i say nothing i mean at worst £75 and you`ve got a new one.If i used mine as much as some of the guys on here i would keep spares of both items,you can replace them yourself for the time it takes to make a cup of tea so no downtime.