Personally, I have never had my RCS climb out of their tank. Mine are constantly scavenging and picking things off and amongst my java moss. My shrimps also always pick and eat flake food that has sunk to the bottom (I keep mine with a school of Endler's Livebearers). Good luck with your set-up.
While RCS will eat anything, it's important not to overfeed. They don't eat very much, so if they don't fully consume something in 3 - 4 hours, take it out of the tank. I tend to feed my shrimp about every other day - this gives them time in between feedings to consume biofilm (algae, bacteria, etc. that grows on all surfaces) throughout the tank, keeping it nice and clean.
I also have not had any shrimp (or dwarf crayfish) climb out of a tank. I generally try to cover my tanks as much as possible to avoid evaporation, but an RCS could easily escape from most of my tanks.
I feed Mosura Excel, omega shrimp pellets, and occasionally bits of HBH algae wafers. The algae wafers do have copper in the ingredient list, but it's apparently not enough to harm or bother my shrimp in any way.
rec cherry shrimp are not able to support their bodies out of the water. They will generally only jump out if chased by a fish or there is something bad, like copper, in the water.
Mine seem to eat just about anything. I give them algae wafers, Hikaro crab cuisine and a mix of fish foods. The seem to like tetra color bits especially.
UPDATE:
My shrimp arrived healthy and happy on Wednesday!
I LOVE them, it's so fun to go see them dancing around on the moss ball and climbing all over the structure!
I feed them a little crushed fish food once a day when I gave them an algae wafer they didn't even touch it! I am afraid to take it out though for I might get a shrimp!
They are CUTE little buggers, and good hiders I only see 1/3 at a time LOL!
Good luck with your set-up.
