I'm probably like most in that I have used a variety of sizes, but I seem to have settled with 7 1/2's. Size 6 is also good in my experience, particularly if shots are a little longer, but I have shot more 7 1/2's for crows than anything else. Oh yea, I'm one of those people who have used #9's as well, not much, but a little. They worked ok as long as shots were close. I've used 8's more than 9's and I seemed to have more cripples with them, so I just continue to use 7 1/2's. But hey, whatever works, works, right?