You aren't going to get any recoil benefit in the 9mm, with the .40 a little bit.
The PC triggers are nicer. I never noticed any noise difference but it's been decades since I had to use an indoor range.
Cleanup of the PC isn't bad at all if you clean regularly. What junk there is around the ports is soft powder fouling and it wipes away easily.
I suppose if you only clean once a year the fouling could get hard.
I liked my PC well enough, but like my .45 Shield better. the .45's all come with nice triggers, PC or not.
Sights I usually end up changing no matter what.