I fly two different ones. Both true out at about 145kts on about 14gph. The two bladed one cruises a touch faster than the three blade and flies a little nicer as it is not as noseheavy. This is how Cessna should have built the 182. Also the three blade has a Robertson STOL kit and the two blade has VGs. I like the VGS better as when you get it really slow you have much better control authority thasn the Robertson. Don
Another friend has a O-550 300hp in his 56 182 jump plane. That is a real rocket ship. Climbs like you can't believe and 155kt cruise if you want to burn the fuel. Texas Skyways has an IO-520 conversion also but it makes the airplane even more noseheavy than it already is. Don
I too am looking at my options for engine swap in a 182Q, I'm considering the Texas Skyways conversion. However I have learned that western skyway will do swap with 520, same HP as derated 550 Tx Skyway uses.
My 182L is the IO-520 version of the Pponk. I burn about 14 gph at 135 knots, 21 inches and 2200 rpm at 6K to 8K MSL. This combination also allows me to keep CHT at 375 or less, and EGT at 1375 or less. Its very easy to increase to 145 knots if I am willing to burn 15 gph, but honestly I don't want the flight to end any sooner. Where it really pays dividends is in high DA situations.