I have a Fluke 43B single phase unit and a Fluke 435 3 phase unit. I bought the 43B new in box from ebay for a reasonable price. The 435 costs more than each of my first two cars.
I've had good luck with both of them. We had a UPS with an inverter that was unpredictably failing and going to bypass, so I connected the 43B to the inverter output in transient record mode. We sent the captured transient to the UPS manufacturer and they promptly diagnosed the problem and sent a serviceman the next day to replace the inverter and inverter control board. I've done some 3 day and 7 day logging as well as harmonics measurement with the 43B as well.
I bought the Fluke 435 to use as a portable 3 phase meter and logger to capture inrush events, perform load studies, and troubleshoot. I've used it a few times but I'm not as comfortable with it yet as I am with the 43B, mainly because I've had the 43B longer and have more experience with the unit.