You might notice a difference on a .40 with standard loads. Maybe.
On .40 Major, yes; but the only place that matters is IPSC or USPSA and it would throw you into Open against purpose built guns with optics and huge magazines.
The cost would be high and who knows what it would do to function.
I wouldn't risk it.
Not on a big heavy 9mm like that. Leading SigSmith Bruce Gray already calls a plain P226 9mm "like dryfire with noise."
Aesthetics? In the eye of the beholder. I don't think a lump of metal with some holes in it on the muzzle of a gun is attractive, just functional... sometimes.
