Oh, and they didn’t include any paperwork in one of the deliveries, which further complicates the return.
Didn’t think you bought stuff very often, and this this verifies it :-). I’m guessing this is a big, important purchase for you, to be to making such a fuss about it? Go into your orders, click ‘return an item’, print a return slip. It’s not difficult. Given the incessant moaning I doubt they will mourn your future custom. In fact, they might throw a party :-).
Seriously, I have found SP’s return process to be very efficient. Given the amount of new items they continuously advertise and turn around, this sort of thing is bound to happen occasionally, and they are in the hands of the supplier.