It's really SO worth it! And it's quite 'easy' to do, so you can even save up for it a bit longer and do it while being older / less fit. You can book your own room on the train and I'm not the best sleeper, but I've slept quite decently at night on these trains!

I wasn't bothered by train travel in the UK, but as you travel you're almost never in a hurry :-) Train to Inverness had a 55 minute delay though, so if that happens too often I can imagine you're not a big fan ;-)