There are a lot of things I agree with here already and some that don't have so much to do with a "good" dive op as one that fits my particular needs and desires. YMMV
I do want honesty. I want to know, before I book, all of the details like group diving, allowing a diver to set own pace/time/depth etc or if it's a dive plan, policy on coming back up when one diver is low on air etc. Only if I have that information before I go diving can I determine if the operator suits me...if I don't ask and then find things aren't to my liking I can hardly hold that against the operator, no matter how much I might want to do so!
I do want honesty. I want to know, before I book, all of the details like group diving, allowing a diver to set own pace/time/depth etc or if it's a dive plan, policy on coming back up when one diver is low on air etc. Only if I have that information before I go diving can I determine if the operator suits me...if I don't ask and then find things aren't to my liking I can hardly hold that against the operator, no matter how much I might want to do so!