I tend not to use those deals as they end up charging loads of interest and you pay way more for your product than if you had bought it outright.
Also just read that from the 1st of April only 18-25 years olds can apply for this....arghh I'm 25 at the end of May!! haha
The only scam with regards to offers like these is that they're kind of counting on the fact that if you don't have enough money now, you won't have enough then. You might start off really positively and aiming to save enough, but things always happen to mean that you might have to spend some of it and if you don't have the full amount when they ask for it, you'll pay hefty interest over a longer time.
Some companies (including DFS) don't actually bother to tell you when your "interest free credit" is up, meaning that a lot of people just "forget" (easy to do over such a long period of time) and then they'll receive a letter a few days after it's up saying "right you now owe us _____" and you have no comeback, because at the end of the day you signed the papers.
It's possible for it to be a good deal, but only if you're REALLY careful, and also positive that you would be able to pay the full amount within the time period specified.
maybe it's legit if the arts council are involved - suppose you could check if the same item is available for the same sort of price on a "buy now - pay now" basis to see if the ticket price has been inflated.