I do!
In studio, metering becomes critical when dealing with more than just one or two lights. When you have a shot with six or seven lights, and you are trying to match intensities, it is far quicker to meter each light and adjust than to tweak as you go based on the on-screen results. When shooting with lighting on location (with the sun) I can't imagine not using a meter. For one, you can't rely on your on-screen results in daylight (which you can't see). And secondly, you are often going for a certain ratio vs. the sun to achieve a desired effect. Add more than one light outside and the meter becomes all the more indispensable. Distance from your subect and different modifiers also give widely different light output outside. For location shooting, trust your meter.
I relate the use of a light meter for a photographer to the use of a tape measure for a carpenter. Tell the carpenter that you want him to build a table out of some uncut pieces of wood, 30" in heigh with a top surface 24" x 38". Then, take away his measuring tape. I'm sure an experienced carpenter could build you a table, but it will be less accurate and take him longer without it. Or, he'll just laugh at you and tell you to give him back the tape. 30 years of experience bulding furniture doesn't mean he can accurately visualize what 38" is.
Not only do I use a light meter, but I also use the new Sekonic C-500R digital color meter as well, so that I dial in my K temp and tint before shooting. No more white/gray cards or MacBeth color checkers. I meter, set it, forget it and have dead-on results with no PP tweaking. The carpenter's moto is measure twice, cut once. I believe the photographer's moto should be meter twice, shoot once.
All that being said, I think that Marc's table top work in studio is stunning, meter or not. Experience is something there is no shortcut for.:salute:
Oh, and the 758DR allows you to calibrate your camera's true ISO and gives you a visual display of your dynamic range, before you ever take a shot or peek at your histogram. There is a video of this on the Sekonic blog.
David