If you're going to get CPOs, just know that it's very likely that they will try to catch your shrimp and fish, they're just not very successful at it. However, I'm almost certain one of mine took out a neon tetra...it had to be a fluke though, perhaps the neon got stuck in the plants.
I've never seen them catch an Amano, Neo or Card shrimp, but they try and try. They did eat one of my ghost shrimps, but that shrimp was probably sick or molting. They're too slow.
Currently, I have my CPOs with some CRS and Cherries. But, you have to be OK with the fact that it is possible they could catch your fish and shrimps.
About breeding.. in my limited experience, my female has berried 3 or more times, but I never saw any young. There should be enough hiding places, so I'm not sure what the issue is.