The mattress has arrived, at half past six this morning (which no doubt is "between 7am and 2pm" as promised). Except that it's not a 180cm x 200cm mattress. No, it's two 90cm x 200cm mattresses sold as a unit. Despite no word of this small detail being mentioned in the catalogue or visible on the showroom floor.
Now, I can return this (and probably make them eat the delivery charge if I try hard enough), and have no bed by Friday. Or I can put up with this fucking crap object. Fuck.
Update, 2:20pm: Just called to whine. They took all details (including that I want the delivery refunded) and said I will receive a call back from the store within 72 hours, whereupon I can argue further. I'd rather the lump of cash now, but this way will cause them slightly more pain, which is of course more educational.