Stopped by store today, Matt has an awesome Rainbow Carpet anemone. I think this is only the second time I've ever seen it- heard it's very rare. This would be like a penthouse for my clownfish.
I had 2 AI sol, but didn't like the coloration on my sps. I just switched backt MH, and thinking of adding a little of "full spectrum" led for more color enhanement.
In my opinion (I bought one), one is probably enough. You just have to make sure it is Securely attached to the cabinet. Since it is only $10, however, it's not that much more to get two.