I had 2 amano shrimp with rummynose tetras and a dwarf mexican cray for months with no problems....
I then bought 2 tiger shrimp, and 2 cherry shrimp... the cray ate the cherry's, one of the tigers, and one of the old amano's within an hour of the new ones being put in the tank. That was 3-4 months ago, and the two leftover shrimp are still fine.
Someone said something about celestial pearl danios... I added a school of 7 of them about a month ago, with 3 emerald dwarf danios (apparently very closely related). No problems.
I've never seen fish attack any shrimp in my tank... just my experience, though.