Look chaps, if we're comparing how big/how far/how fast/how cheap, can we please use figures that make sense? How about taking a leaf out of the motor trade and use miles/gallon (or equivalent)?
For a starter, it would appear that the RV8 can give 5.95nm/l, the SC 6.1nm/l, the RV9 5.7nm/l and the MCR at 7.45nm/l. Of course, I'm assuming everyone has quoted TAS and USG (where given in gallons).
PS. I still like all the aircraft quoted above.