spark plug gap? .39-.59

I was wondering about the gap on our cars no one can seem to agree with each other about this. I have seen posting about there gap from .39 to .59. I was wondering what advantage/disatvantage making the gap bigger or smaller? I have mine at .54 which is stock gap right? Would it be better to close it up or open it up? Maybe some can help me out on this.
thank you

There are a lot of reasons to change gap. If you aren't pushing a lot of power or have 15 lbs. + boost then I would leave it as is. If you have higher boost numbers then you may want to lower the gap to about .45 or so. I have heard that the increased cylinder pressures actually blow out the spark and causes a misfire.