much more!
and you can get about 6-8 pairs for what 1 pair of greens will run you.
They are no where near as sysitive as the greens, lay a good number of eggs each year, where greens lay very very few. They dont have to be kept in as spotless and imaculate pen conditions as greens, handle winter a little better, and are no where near as flighty, you can actually walk up to them, greens you have to be sneaky with, they will stress out and or get extremely flighly when they see you, very similar to green peafowl, but worse.
Greys have that beautiful feather patterns and marking, just in a grey form instead of green.
I would HIGHLY recommend you start with them and work your way up to the ceylons and greens in a few years, IF you still wanted to try them after you have the greys.
Good luck