Not all Hammers (actually, Anchor) are branching. Some are termed "walls" which describes the skeleton nicely. It should be obvious which you have by looking at the skeleton. In my opinion, the branching type are more hardy - if a head gets damaged you can just snap it off. With a wall type, if there is tissue damage, it can rapidly just progress right down the entire "wall" of tissue and you'll lose the entire coral.
Often times, clowns hosting LPS
kind of dooms the LPS
. Depends on the coral and the clown, but many times the clown just "loves" the coral to death by not letting it expand or by constantly irritating or damaging it. Just something to watch for... not that you can do anything about it!