I purchased a "guaranteed" next day service. The package was delivered two days late. The 'tracking' feature was ridiculous. I lost money as a consequence of late delivery. The Post Office rejected my claim for compensation on the grounds that I did not read their T&Cs or purchase their 'consequential loss insurance' (which was not offered and I had never heard of!). It should be illegal for a company to describe a service as 'guaranteed' if it is not guaranteed (or insufficiently insured, as in my case). The Post Office and Royal Mail are essentially monopolies. They were better as state owned organisations. Hopeless customer service.