Great comments. I learned something new from you.Typically I will start with a 1 lot routed to the CBOE. I have found the generally they will give me the best fills. Say a call option is quoted at 1-2. I wouldn't assume the mid point is fair price, I would first look at the strikes around it. For example if the strike just below is quoted 1-1.6, you would know that the mid price of your strike is too high. If this is the case, and I wanted to buy the option, I would first put in a 1.10 bid and wait a couple of seconds then cancel. I would then go up slowly until filled
I usually looked at IV at the strike and those above and below to gauge if it is miss-priced.