I don't have a problem with loading mine either (XD-45c). I do remember using a my instructors duty G17 in a fighting pistol class a few years ago when my trusty 1911 broke an ejector and didn't have very much ammo for my back up gun with me. Anyway, his G17 mag's were so tight that loading the last two rds was just stupid. It actually bent my thumb nail back and caused a blister by the time the class was over. my thumb looked like I hit it with a hammer or something.
My G17 I have now (didn't have then) is no problem loading without assistance tho. It's a little stiff with the last two rds but nothing like my instructors G17 was. Kinda strange how they are not consistent no matter the brand.