Now and again (seems mostly after a long journey) the car struggles to start (9k miles & about 1.5yrs old).

You have to hold the ignition on for longer (aprox twice the length) and it starts up as normal - except once... After getting it started it rev'd and died instantly, managed to get it started again, but this time had to rev the engine, to keep up running (for 20seconds-ish).

Any ideas whats the cause? Planning to tour Europe and don't want it to die on me lol

It could be a variety of reasons. I would book it in to a garage that has VAG COM and see what fault codes are bought up. That would be the easiest way of finding it. Its probably something silly like a loose fitting connector. I would go into your engine bay and pull and push all the connectors on the car to see if one is loose. It sometimes works and sometimes doesnt. Hope you get it fixed!

try depressing the clutch - it may catch quicker. Sounds like a knackered or dirty sensor, maybe even faulty imobiliser.

D