How big a difference, in felt recoil is there between factory ported glocks and the standard models?

I have a standard glock 19 for duty use, and a glock 26 for off duty carry. I am thinking about getting another 19 for home defense (the wife loves my 19 duty gun). Night sights and a light are a must, but how big a difference does the factory porting really make? Does the porting drastically change felt recoil, or does the added cost out weigh the overall gain? I usually have my 26 and 19 loaded with speer gold dot 147+p hp's. In the little glocks, the speers really pack a bang. The recoil has never really been an issue for me. But if the porting makes a MAJOR difference, it may be worth the money for my wife's gun. Do the porting holes open up the slide innards to a major dirt fest? I have never even held a ported glock, that's what all the questions are about. Thanks for any feedback!