From what I can tell, I did a search on this same thing and asked around some of the 3rd years a few months ago and noone seems to know how accurate Qbank estimates are. My Qbank estimate correlated well with my CBSE score, but the jury is out on how accurate those are as well. Also some people do tons of Qbank before studying and some people do it all after they have reviewed a ton. Some people do random 48's, and some do subject specific right after studying that topic. I don't really see how it could be that accurate of a predictor. Like the average qbank score is a combination of people who have studied a ton and people have just started studying whereas most everyone has studied a fair amount before taking step 1 so you can't just say that the avg. qbank score is equivalent to the average step 1 score, ya know? Basically I think everyone is just guessing and you are only going to get anecdotal experiences. Also most people stop reading this forum after they are done studying, so most of us are realllly just guessing b/c we haven't even taken the test yet.