i have the Mvvs .40 for a year now with over 200 flights on it.
plenty of power with a apc 11*5 ( no one at my club flies a 40 class engine with a 11 inch prop .. not even the os 46fx owners i do not know why)
i have the old 3216 carb which runs great but now changed to the newer version ... runs even better.

also have a .45 with a 3217 carb.... this is the greatest carb around for the engine class... very linear transitions and very low idling is possible, no midrange misses whatever ..

I run homebrew 80/20 fuel with a twist of nitro at 2.5%, os 8 plug , at sea level in hot tropical climate.

most people tune the high speed needle like japanese engines ... keep on leaning till peak rpm with plane at vertical ...
i tune for high speed at horizontal ... and back off a bit . Check rpm WOT at horizontal and then vertical ..it will gain a few more rpms .... if it holds then do not adjust anymore. it will unload further when in flight.

if you did the tuning of high speed needle with plane vertical then it will sag at horizontal because of smaller fuel supply when the plane goes up in the air.

just my observation...