At $500 to $600, the H&Ks will be out of your budget. In that range, I would probably be looking at the XDs, the SR9c, Baretta 92FS or PX4 or a CZ such as the P01 or 75.
I know you had already listed, or had suggested to you, several of these. I think you are on the right track to find what you want by trying them and seeing what fits. As far as I know, most of these are not ammo-sensitive.