We're considering train tickets from Edingburgh to London well in advance to save money with early booking discounts. However, the ticket provider Raileurope's website (via Rick Steves' site) includes "This ticket is not guaranteed on any train and availability may be limited." Does that mean buying the ticket is pointless and we may not get seats?
Also, does anyone have any tips on getting from Kings Cross station to Victoria station (Belgravia) once we hit London?