You might also want to keep in mind that a stock like CME will most likely continue making new highs and perform extremely well as we close out this trading year. There are people out there who will need to play musical chairs or simply disassociate their losers at some point in December and be jumping on a CME band wagon. Definitely give yourself some wiggle room on the call side. An extra 10 or 20 point bumper cushion might not hurt that much. But than again this whole discussion could be moot if CME blows up to $600
These credit spreads aren't for the faint-hearted. In essence one is 'borrowing' the maximum potential profit at the initiation of the trade. Then, if the position unfolds against one (vertical credit spread), this whole 'profit' is returned immediately and then some. I can't remember the number of times I've been stung by the critters. The rr generally sucks if far enough otm. The only saving grace is the double vertical credit spread (IC or iron fly) and that's only because one is right on direction at least 50% of the time. That's great provided the risk reward is at least 1 to 1 or better. Good luck. daddy's boy
With my research into these credit spreads I find the 1:1 risk reward ratio is for ITM and slightly OTM options and/or earnings is coming up.