I will be visiting London later this month and need some information on the pay as you go Oyster Card. I understand in general how it works but I want to know the following:
Can I buy an Oyster card at the Heathrow tube station?
When I am leaving London can I get a refund for the unused funds?
Also, I would like to hear from anyone who has used the Oyster Card to see how they liked it and if they thought it was a good value.