The fluke 179 has more measurement functions, conformance to the latest safety standards, and a much larger display with backlight that's easier to view.
Electrical safety
all inputs are protected to measurement cat iii 1000 v and cat iv 600v. This meter can withstand transient impulses in excess of 8000 v to help protect you from arc blasts resulting from surges and spikes.
Why you need a true-rms multimeter
electronic loads with switching power supplies or inverters distort the ac voltage and current sine wave
non true-rms meters can measure up to 40 % low
true-rms meters make the most accurate measurements when the sine wave is distorted