I would give them zero out of five if I could.
My mother ended her £15 monthly contract with them in March, but they still decided to take money from her bank account.
They took £25 in April and are asking for £15 for March, she hasn't been using Vodafone for those months. It was pure chance that she spotted it or god knows how long they would have stole from her.
She will be sending a letter to her bank to cancel the direct debit from their end, and I suggest that anyone ending their contract with Vodafone do the same to make sure.