thats a tough call, I would go for it. Most tickets are non-refundable but I would buy it in enough time that you can get a good price. I know there are some sweet prices on flying to london right now (its off season there) so maybe if you flew into a country that has cheaper airfair and then took a train into the cities you wanted to check out, if you haven't been over seas you'll realize you use the train alot and you can cut across europe quickly and cheaply via the train.
I would think about it, its always worth an andventure but thats IMO. Whats money if you can't spend or enjoy it? Then again I'm not the best example, when it comes to money
so dont mind me.