More??
Its got to be 13-15 GPH and its an IO 540 so the engine and prop running costs will be more than the IO360 160 (double would probably cover it).
Which is a shame because the 260 firefly is lovely for aeros. The 160m is barely capable of takeoff and aeros is a protracted and always downhill affair.
If you arent doing aeros then the 160 is a fine cross country machine and its doubtful you'd need the 260.