I'm sure what he meant to say was, you can use a grey card to get the metering as well, by shooting the grey card then checking your histogram. I've used this technique several times, mostly when I forget my meter or the battery was dead on the meter. But you can do this very cheaply and quickly once you get the hang of it.
As for meters, I've had the Sekonic, 308s, 358 and 558R. Loved them all. Currently down to the 558 and 308. 308 is tiny and goes in my bag when traveling light.
Did you get 2 of the same light ratings? If so, you can get close to the right ratios just by the settings on the light and keeping an eye on your light to subject distances. Remembering that twice the distance equals half the light etc... If you have differing power heads, just do the additional math and your set.