The advantage of London
Travelcard is, that it is valid for the specific number of days, within the specific chosen zones, which is good if you travel a lot during a short period of time.
For example when having a 7 days Travelcard, valid for zones 1 and 2:
- If you travel a lot every day, then Travelcard is a good option for you
- If you travel 2 times a day, only 5 days out of 7, then Travelcard is not the best option for you, because currently it costs £38.40, but you will not use it enough and it expires after 7 days
The advantage of
Oyster card is, that it is not valid only for a few days and you can travel within the zones you want. Simply said, you are charged when you travel. Oyster card also has a "daily cap", which is the maximum price you will pay in a day. Oyster card is better, if you don't travel many times a day / every day a week.