After using one I will never even worry about the camera metering system.
At a wedding shoot, I go to the alter, push the light meter button, adjust my speed and aperture to the readings, perfect exposure to the pont where maybe a very slight adjustment if needed in post. Go outside to shoot more photos, same thing the light meter works great in the sun, under shade, heavy back lighting, no need to keep testing and looking as the LCD as with the in camera metering.
I bought my mint Sekonic on Ebay for $100.
Bob P.