For the street or drag strip, I don't see how you can run the car hard enough long enough to run into heat issues. So I don't see an issue with street use.
In my experience, the car can barely handle being pushed for 20 min in stock form. I can get the car to pull the redline from high oil temps. If you think this acceptable, read no further.
I can't imagine putting 5-7psi on it will make things run cooler. Over the long term, you significantly reduce the service life. Not to mention dealing with heat soak and having to dial it back to keep the car from overheating.
You won't see the problems now but it's for whoever has the car later in life. The simple physics is you put more load on a piece of metal and it fatigues faster.
2013 F30 328i Melbourne Red
2011 E90 M3 Monte Carlo Blue
2004 E46 M3 Imola Red