yes definately follow Buenchico's advice. I used the stanstead express for the first time last weekend and worked out great. All very straight forward. We booked before hand and it cost �23 for return journey. Only thing best check for planned maintenance. We were travelling Saturday afternoon and then returning Sunday afternoon. We heard people being told they would not be able to travel Sunday morning due to maintenance - there had been no note of this on the website but fortunately did not affect us. It took us into Liverpool St Station - we then got on the underground. Best to work out before hand where you are travelling to then you can work out the best line to take - actually was far more straightforward than I realised, with a bit of planning.