Microstructure on synthetic flies is much cleaner than trading an ITM leg. I trade 2-3K contracts a day (in/out) and my average fill on all spreads/combos is 0.3% off mid as a price taker.
GOOGL 1700/1800/2000 231 put fly = 2x1700/1800 bull put verts x 1x1800/2000 bear call vert (combo). I don't have the numbers in front of me but IIRC the Px-improvement is on the order of 0.1%.
GOOGL 1700/1800/2000 231 put fly = 2x1700/1800 bull put verts x 1x1800/2000 bear call vert (combo). I don't have the numbers in front of me but IIRC the Px-improvement is on the order of 0.1%.