if you put a led fan on the p160..

in the front.. would the lights shine through the fan grill? o.0

oh.. and if the exhaust fan is 1600rmp.. should the intake fan be about the same speed? does that matter? o.0

I would think you get a minimal amount of light shining through the grill. Second rpm's of the fan is not as important as cfm. Some fans move more air at slower speeds then others. I have mine set up with identical intake and exhaust fans. However they are adjustable speed fans and the front intake is on full speed and the exhaust is on min speed. Remeber you have an exhaust fan on your psu also.