Ideal Conversion Rate steer

For all you experienced feeders out there.....what is the ideal conversion rate you like to see in a steer?  One that is still growing /on grower ration ....roughly 4.5 months to go.  I realize it's a complicated question.......

At least 8 -1, any thing 7-1 or better is great. We never really went over 25 pounds a day of grain, had some everage 6-1 for a month or better. That last hundred pounds they slow down but fat weighs less than muscle.

When I hear of calves eating 36 pounds of feed a day and there only gaining 3 a day that is 12-1, your throwing feed away. I read a study where the calves on free feed actually had a much worse conversion rate as well as daily gain then the calves on a controlled ration.

Thank you, exactly the info I needed.