Hi everyone, I would appreciate guidance about the best web site to use to purchase an open return ticket between London and Cambridge. My travel date is 14 January. My goal is to visit the Fitzwilliam Museum for an exhibition on ancient Egypt, have lunch at Dishoom's Permit Room, plus a bit of a wander through the town. I want to book an open return ticket in case I decide to stay longer than anticipated. I compared National Rail, which directed me to ThamesLink for the actual ticket purchase, and Great Western Railway. They both offer the same itinerary for the same price of 48.50 GBP for an Anytime Day Return ticket.
Depart Kings Cross 8:42 > Arrive Cambridge 9:13
Depart Cambridge 14:42 > Arrive Kings Cross 15:32
Should I purchase my ticket through ThamesLink or GWR?