PSMH lamps put out more light per watt than standard. You can usually replace a standard 400 watt MH with a 320 PSMH. My experience on restrikes is they are a couple of minutes faster.
As for higher current draw on startup, the PSMH ballast does draw more current than a standard MH ballast. However, the starting current is less than the operating curent, so there would be no problems at startup.
Few things are harder to put up with than the annoyance of a good example.
