Well, there is lot of tangs on the list, that are quite uneasy to handle in tank. But I like mostly the two, I wrote in my post. I think clown tang would be not so hard as achilles or powder blue tang.
Powder blue is very sensitive on water quality and stress. And needs lot of place and hidings, to ensure, he will be not stressed by other fishes. Unfortunately in my country I can get these fishes mostly directly from Bali/Indonesia import, so they are still shocked and stressed.So after transport home they need lot of care and quarantine.
Achilles is not so transport sensitive, but usually does not want to eat anything and depends on the piece, if it will be ok or not.
I just want to make ideal conditions for them, so they can be fastly acclimatised and moved to my display tank.