As far as porting goes most people either like it or they don't. General consensus is that porting isn't such a good idea for a carry gun. What Webleymkv said is good info. Yes there's low flash but debris could and would possibly strike you in the face or eyes under certain conditions especially if the gun would be used for self defense.
Many guys who have ported guns (revolvers at least ) bought them that way. They usually get a deal since it seems porting generally lowers the resale. I bought a ported FA 454.The porting really did help hold the muzzle down at the expense of shooting gasses/ lead/ lube/ not only up but to the left and right. I sent the gun back to get the ports cut off. I like the gun much better now both functionally and aesthetically and it's easier to clean too. This may not help answer the OP questions but it's my story and I'm sticking to it