Well, this can be a slightly difficult question to answer. For a longer hitter, it could be easier because you'd be hitting a shorter club. But ANYWAYS,
I'd probably miss it 20% of the time? 150 is a stock 9 iron(fade) for me, so it's a little easier than if you're hitting a 7. But My BEST key, as in, what helps me the most, is picking a dimple above the equator of the ball, towards the right center, and trying to hit that dimple. My normal miss is a pull. So left would be my miss.