Best is whatever lets you bang out your presentation and get back to your customers.
Worst is time spent wondering what software, what background color, what font, what socks to wear, or a million other distracting but irrelevant details that trick you into thinking you're accomplishing things.
Never is how many times anything important is going to hinge on what software you used to distill your story, numbers and potential into a short presentation.
It's an absurd question. You might as well ask "Which socks should I wear to the meeting?" Because if your answer matters in the end, it's because you used something extreme. The only time this would matter would be if it was the reason you didn't get funded/interest. Who cares whether the presenter uses Prezi, PowerPoint, Keynote, etc? No one. Who cares that you wore black wool socks instead of brown polyester ones? No one. But if you try to do your presentation at the command line, for example, you're done. Or if you wear crazy runner half-leg socks and make a point to show them off multiple times during the meeting, you're done.
You should have better things to worry about. The fact that you don't should worry you.
Worst is time spent wondering what software, what background color, what font, what socks to wear, or a million other distracting but irrelevant details that trick you into thinking you're accomplishing things.
Never is how many times anything important is going to hinge on what software you used to distill your story, numbers and potential into a short presentation.