I to thought it was going to be to big, even after holding it in person... But, I bought it, shot it and now my hand and the gun feel to be just fine. I can tell you this, I have held a USP 45 (not at the same time as the FNP-45) and I put the gun down and said it was to big for me, I didn't buy it. My point is, I didn't have the same feeling when picking up the FNP-45, yes it is big, but it didn't feel big for a 14 round gun, so she came home with me. I would bet it all has to do with the grip of both guns, the HK grip is blocky (I would say to much distance/long back to front) and the FNP just feels right (1911 grip angle?). For me on the FNP I do use the flat grip insert, it seems that it gives me a better finger on the trigger in DA, I'm not sure why, because the swell is more on the lower part of the hand.
Size of the gun is large, but I have a concealed carry rig (holster/2 mag sheath/belt) being made right now for it from
http://www.littlebearholsters.com . I think she will carry just fine. I am a big guy (250/6'2") with a 43 year old gut to help hide it, but I would say my hand size is about a "small" large if that is possible (I don't know my true hand size, but I would say 8+/-).
But all in all, yes see it in person, just don't go blind and buy it from a on line store with no touchy/feely.