the max amp or size and cost of your meter depends on what you are measuring. If all the loads come from 100 amp circuit breakers or less, any of the ones you listed would work. if you are measuring 600 or 800 amp loads then you need the greater capacity.
Also true rms give you better accuracy but if you are only checking non plc controlled motors you do not really need it. For any load with harmonics you need that accuracy
