As someone who travels a lot I can tell you that you can book a round trip and not check in for the return flight for sure. It's yours and if you paid for them already, they don't really care and if there are people waiting for the flight they might resell it if you don't shop up at the lasy minute. Honestlyround trip as are usually cheaper so if you can find one, then hooray. I hope this makes sense. Fingers crossed you get to see Darren!!