I would test for a ground fault. A meg-ohmeter is best for this but you can get a reading from a ohm meter as well. You should read above 500k ohms if it is ok. However it will operate until you get to about 20k ohms to ground and I would not pull a pump that measured 100k or above until it...
The constant pressure pump will save you money on electricity and you will get a 3 phase motor that will normally outlast a single phase motor. Lets not forget about the space you'll save on the smaller pressure tank.
It is true, all drives are not created equal. I would suggest installing a...