Although it is not our current duty round at the PD I work for (current 9mm duty round is Fed 124gr +P HST), the 124gr +P Gold Dot was our former duty round and had been issued for quite a few years. We have never (yet, anyway) had an Officer Involved Shooting, so I can't tell you how they work from first hand experience, but experience from other Departments shows that it is a very good round, even in shorter barrels. We have quite a few guys that carry 9mm Shields for off duty guns and the Gold Dots always functioned flawlessly.

For us, the reason for using +P isn't because of higher velocities or anything like that; it is because the extra "oomph" of the +P cartridge should, hopefully, help reduce malfunctions in the event of having to shoot when in less than optimum positions or if the Officer isn't holding the gun as rigidly as they should in the heat of an armed encounter to make sure the gun functions as reliably as possible. Admittedly, there isn't much extra velocity, but every little bit helps.