I think the service you receive from the NHS differs vastly depending on which trust you fall under. My experiences have mostly been bad, from mental health issues to physical complaints, and from GP services to hospital services. I'm very grateful that we get free healthcare, but I think there's a long way to go to make sure you get the same level of service no matter your location within the UK.
Sometimes I think I would actually prefer a health insurance system where you have to pay a contribution towards the services but you have a better experience when it comes to treatment and diagnosis alongside having more say in where you access your treatment.