My hermit crabs keeping knocking them down. I think the hermits are using the cap frags as ledges to climb up and down the rock. Other then that a few looked like they might bleach a little, been target feeding each time I see the bleaching start. So, that is under control right now.
It sounds like you lfs doesn't know what they are talking about, monti caps are peaceful and can be placed next to each other and other peaceful corals. They will tend to try to out compete other corals for light, by over-growing other corals, but not stinging. You can graph multiple caps together, they will end up growing into one multicolored coral head.
Overall, they are fine. Some are just starting to grow and attach to the rock, which is good b/c I'm tired of reaching in the tank every day or so to glue one or another back onto the rock.
It will be interesting to see which one grow faster and if any correlation can be made w/where on the rock they are located (top, middle, bottom).
My photos may not show the colors well, but there are four different colors down the side of the tank:
Grape Capicornis (pink/purple)
Orangade Capricornis (orange/red)
Purple Smoke Capricornis (deep purple)
Shady Lady Capricornis (olive green)
Thanks for asking