For obvious reasons stemming from that case down in Florida we ain't sposed to talk about here I would not suggest using a Kel Tec PF-9 for EDC or SD if you live in a gun unfriendly area. I can just hear a NY or CA Prosecutor now "He used the same gun as this racist child killer! He must be a racist child killer too!". I really think this all comes down to knowing where you live and the "mood" of the community if you will. Myself being from Illinois nearish to Chicago; I would be very concerned legally speaking if I needed to defend my home against criminal "youths".
Does it make any LEGAL or for that matter common sense that people get railroaded because of the type of equipment they are using; rather than a substanative argument about the facts of the encounter leading up to the self defence shooting? No. That poor guy in Arizona with the Glock 20 comes to mind.
Does it happen ? Yes.
My SD handgun for the home is primairly a P229. Very similar guns can be or are used in PD's in my area. I also mostly load up with speed gold dot's these days; again common ammo that I am sure some local PD's use. I would not STOP using it if I found out all of the local PD's around me switched brands; but on the same tolken I am not going out searching for the most deadly expensive exotic 9mm load known to man.
I think the bottom line in all of this is if you have an aggressive prosecutor who has taken a case to the point where your choice of a defensive weapon is in play that you are already in serious trouble. If they are digging 20 years into your past to see if there is a single person with a single bad things to say about you, or about any off color jokes you ever told; you are in trouble. There is nothing you really can do about that except midigate the risk based on where you live.
If you live in the heart of the anti gun empire like NYC, Newark or Chicago it might not be a bad idea to see if you can make the exact gun and ammo choice used by the local PD work for you. That being said I would NEVER admit under oath as others have pointed out the fact that the equipment is police issue factored into your decision to select it; less that fact be used against you.