I have both the 9 Pros: 4.25 bbl and 5 " bbl.
Both triggers are the same, about 4 1/2 #. Tthe triggers suit me just fine, being an old revolver shooter. The first pull is long, but if you learn to come back to reset instead of all the way out, subsequent pulls are shorter. Don't evaluate the trigger until it's been shot about 500 times.
The sights on the 4.25 are night sights, making it more suitable for duty carry or personal protection.
The 5" Pro has FO sights, which are great for the IDPA/SSP and USPSA/ Production I shoot. The gun shoots to point of aim with 124gr FMJ or HP minor power.
I was on the 100yd range checking the stability of my handloads in the 5" Pro when a group with a muzzleloading rifle (who could not get a shot on paper at 100yds) made a snotty remark "what do you expect to hit at 100yds with that little pistol?"
On their many trips to search for a hole in their target (in vain) they had left a 2L drink bottle sitting by their target. Knowing that the 9mm drops about a foot at 100yds, I carefully rested the pistol and squeezed off a shot aiming at the cap. THE BOTTLE EXPLODED.
As to aftermarket "match" barrels for the M&P pistols, they usually just have tighter chambers. One of our shooters bought the most expensive "match" barrel available, then found he had many failures to feed with the ammo he was using. So he had the chamber jugged out for reliable feeding, negating any improvement in the aftermarket barrel. Oh well, some people just have to start modifying any gun they get.