I have owned two SA XDs , one glock 21, and one glock 21 SF. The only one I still have is the Glock 21SF. I have done some tweaking to the Glcok 21SF to fit it more to me and what I like. There was nothing wrong with the XDs, besides the trigger pull and reset was horrible. I just could not get my trigger finger trained from the Glocks to the XDs, thats just me though. The XD's ergonomics and grip angle were superior to the glock's.
I also liked the wide metal trigger on the XD. I owned the service XD45 and the Tactical XD 45......and in comparison, the service model was just as accurate as the tactical. I dont know if that was a fluke or if I had a bad barrel, but the tactical was no more accurate than the service model. I had no FTF or FTE problems from the XDs, and they shot everything I fed them. On to Glock......
I am a known promoter of glocks.....no I dont work for them , although I wish I did because it would be a better job than I have now. I like glocks for what they are: simple, reliable , tough, easy to train, easy to use/employ, and easy to work on/customize. I do not like the ergos of the glock , especially the grip angle.
I wish glock would add a little more flare to their pistols, and do something about the grip angle. I know some out there that like the grip angle, thats fine, but I hear more complaints from people who dont. I have had no jams or problems from any glock I have owned, been issued, or fired. I have owned over 30 different glocks in my lifetime and I have never been disappointed with their performance. BUT.....they are what they are.
Not everyone likes a gock , which is fine, not everyone likes a toyota. I purchased my glock 21 and loved it. I always felt that the grip was just a bit too big for my hands. I didnt mind, I trained it out and continued shooting the big 21. When the Glock 21SF came out, I was rabid, I wanted it , but no one in my area could get it. I waited for another month or so and finally a shop in another town got one in. I went and looked at it. I had it in my hand for about 15 seconds then I told the guy I would take it. I still have it. I have done trigger work to it and I have had a grip reduction done to it to remove the palm swell near the heel of the back strap. My 21 SF now comes up on target just like my 1911s. Enough about the glock.
I have never owned a FNP, so I cant really say anything about them. I have heard good things about them. I have looked at them at the local shops, cant say much , they just didnt do anything for me.
With what I have said, the XD can be made better ,IMO, with a trigger job or a trigger pack kit. I would keep the Glock 21 SF.