If you are serious about one it would be well worth a call to Mark at little Gransden to chat about them. My knowledge is just in passing. I think the oil burn rate is dependant on if you are doing aeros or not.
Have you flown one yet? Not that I have flown a warbird but the Yak does give you that feel.
MY friend is using his weekly and getting a lot of fun out of it, not the cheapest plane in the world to run, well compared to my little RV anyway but if your happy with the budget a great plane.