I shot several hundred rounds of Federal Champion 115 grain 9mm FMJ in my ported Shield before I noticed "not for ported barrels" in very small print on the box. Now I only use it in my non-ported guns.
That warning usually pertains to ammunition using plated bullets, but there are some caveats.
1) Not all ports are created equal. Ports are made after the barrel is rifled and when the port is machines, you can have some metal roll over on the edges and stand proud in the bore. It's hard to clean that up without lapping the bore to remove it and the manufacturer or gunsmith porting the barrel may or may not have done that.
2) Over time, any burrs around the port will wear down or be removed by some number of rounds fired, and they become less of a problem.
3) Not all plated bullets are created equal. For example, most "bonded" premium bullets have jackets that are in fact plated. However it's a thick plating comparable to a traditional drawn copper jacket.
Plate bullets from Berry's and Xtreme also come in regular and heavy plate jacket thicknesses, with the heavy plate bullets designed for higher velocities without stripping or damaging the plated jacket.
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So in essence, you've got three different classes of plated bullets. With the "bonded" thick plated jacketed bullets they are no different than a jacketed bullet in terms of use in a ported barrel.
At the other extreme, the thin plated jacket on the thin plated bullets can be damaged by the burrs or edges on the ports, and warnings are sometimes made against the use of those bullets in ported barrels.
However, those warnings are based on some worst case assumptions about the quality and finish of the ports in the barrel, so it may or may not be a problem for a particular pistol or revolver.
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Again, the use of plated bullets in Champion ammunition has been sporadic. I bought 1000 rounds of Federal Brass 115 gr 9mm ammo a couple months ago, which is Champion ammo, the "Champion" is just in really small letters. On the boxes, Federal listed the bullet as the "Champion FMJ RN" and includes both the "not for law enforcement use" and "not for use in ported or compensated barrels" warnings. From that, I've determined that "Champion FMJ RN" is Federal speak for "plated bullet".
